Our Price 
$149.95 
List Price $195.00

Ronstan Series 75 Core Block Single Aluminum Rope/Wire Sheave

Availability: Usually ships within 24 hours
Low Price Guarantee!
List Price $195.00
Our Price 
$149.95 
Series 75 Core Block - Single - Aluminum Rope/Wire Sheave

Core Blocks are a true all round solution. A tuned 2-stage bearing system provides excellent performance across the full working load range with an integrated thrust bearing feature and the resilience to handle high dynamic or static loads. Acetal sheave, alloy cheeks and stainless fixings complete the durable package. For reliability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.

Universal Bearing
Dynamic and high static load performance

The Ronstan Universal Bearing incorporates our proven 2-stage bearing system

Stage 1 - Under moderate loads, Acetal ball bearings ensure minimum friction.

Stage 2 - Under heavy loads, where deformation of ball bearings alone would result in increased friction, a sliding Acetal bearing on a polished stainless steel race takes over, maintaining low friction performance.

Additionally the ball bearings are configured to act as a thrust bearing between the sheave and cheeks, preventing the sheave from rubbing on the cheeks and causing friction when the line lead in and out of the block isn't perfect. Particularly important for cheek blocks.

Alloy Cheek Plates
Block cheeks are manufactured from the highest quality alloy for maximum strength. Material optimisation and the cut-away design minimises weight and allows easy fresh water rinsing of salt and debris from the bearings. Cheek design has been further styled with flaring at the block throat and reduced gap between the cheek and sheave, minimising rope wear.

Universal head
The head assembly incorporates a brass bearing washer to provide smooth 360™ rotation of the post and shackle. A set screw arrangement allows the head to be locked at 0™ or 90™.

Shackles are high quality forged grade 316 stainless steel.

Features:
  • Class leading performance and sleek, contemporary styling
  • Excellent dynamic and high static load performance
  • Less than half the friction of the nearest competitor
  • Universal head with full 3-axis articulation
  • Head posts can be locked at 0 or 90 degrees, by using a 2.5mm Hex/Allen Key
  • Central hub hole can be used as a becket take-off or tie-up point
  • Durable alloy Rope/Wire sheave


Applications:
  • Ideal for mainsheet, halyard and spinnaker sheet applications on boats to 14M (46')
  • Various control line applications on larger yachts
  • Aluminium sheave which has a deep groove profile specifically made for use with wire


Materials:
  • Sheave: U.V. stabilized Acetal
  • Cheek body: Aluminium Alloy
  • Ball Bearings: High compression strength carbon black Acetal
  • Shackle, head post & hub: Grade 316 stainless steel


Specifications:
Sheave Ø:75mm(3")
Max. Rope Ø:14mm(9/16")
Max. Cable Ø: 8mm(5/16")
Pin Ø:8mm(5/16")
M.W.L.:1,500kg(3,300lbs)
B. L.:3,000kg(6,600lbs)
Weight:432g(15.3oz)

Ronstan Series 25 T-Track Composite Slide Series 40 BB Orbit Block Stand Up Suits 9mm(5/16") Rope
Star Price$52.95
Ronstan Series 25 T-Track Composite Slide Series 40 BB Orbit Block Stand Up Suits 9mm(5/16") Rope
MFG: RC72536S
Series 25 T-Track - Composite Slide - Series 40 BB Orbit Block & # 153 - Stand Up - Suits 9mm(5/16") …
MFG: RC72536S
Star Price$52.95
Ronstan Wire Block Tubular Rivet Head with Removable Nylatron® Sheave 45mm(1-3/4") Sheave Diameter
Star Price$33.95
Ronstan Wire Block Tubular Rivet Head with Removable Nylatron® Sheave 45mm(1-3/4") Sheave Diameter
MFG: RF103
Wire Block - Tubular Rivet Head w/Removable Nylatron® Sheave - 45mm(1-3/4") Sheave Diameter

Wire …
MFG: RF103
Star Price$33.95
Ronstan Wire Block Ferrule Top with Removable Nylontron Sheave 45mm(1-34/") Sheave Diameter
Star Price$32.95
Ronstan Wire Block Ferrule Top with Removable Nylontron Sheave 45mm(1-34/") Sheave Diameter
MFG: RF104
Wire Block - Ferrule Top w/Removable Nylatron® Sheave - 45mm(1-3/4") Sheave Diamter

Wire blocks have …
MFG: RF104
Star Price$32.95
Ronstan Wire Block Tubular Rivet Head with Nylatron® Sheave 25mm(1") Sheave Diameter
Star Price$18.95
Ronstan Wire Block Tubular Rivet Head with Nylatron® Sheave 25mm(1") Sheave Diameter
MFG: RF418
Wire Block - Tubular Rivet Head w/Nylatron® Sheave - 25mm Sheave Diameter

Wire blocks have purpose …
MFG: RF418
Star Price$18.95
Ronstan Wire Block with Removable Clevis Pin Head Nylatron® Sheave 25mm(1") Sheave Diameter
Star Price$20.95
Ronstan Wire Block with Removable Clevis Pin Head Nylatron® Sheave 25mm(1") Sheave Diameter
MFG: RF418C
Wire Block w/Removable Clevis Pin Head - Nylatron® Sheave - 25mm(1") Sheave Diameter

Wire blocks …
MFG: RF418C
Star Price$20.95
Ronstan Dinghy Wire Block Ferrule Top with Removable Sheave 25mm(1") Sheave Diameter
Star Price$21.95
Ronstan Dinghy Wire Block Ferrule Top with Removable Sheave 25mm(1") Sheave Diameter
MFG: RF468
Dinghy Wire Block - Ferrule Top w/Removable Nylatron® Sheave

Wire blocks have purpose designed …
MFG: RF468
Star Price$21.95
Ronstan Kite Block Black with White Sheave (Pair)
Star Price$10.95
Ronstan Kite Block Black with White Sheave (Pair)
MFG: RF13101-2
Kite Block - Black w/White Sheave

Features:
  • Lightweight durable …
MFG: RF13101-2
Star Price$10.95
Ronstan Series 29 Block Single Narrow
Star Price$14.95
Ronstan Series 29 Block Single Narrow
MFG: RF185
Series 29 Block - Single - Narrow

Features:
  • Lightweight durable …
MFG: RF185
Star Price$14.95
Ronstan Series 29 Fiddle Block Narrow with Tube Rivot Head
Star Price$24.95
Ronstan Series 29 Fiddle Block Narrow with Tube Rivot Head
MFG: RF186
Series 29 Fiddle Block - Narrow with Tube Rivet Head

Features:
  • Lightweight durable …
MFG: RF186
Star Price$24.95
Ronstan Series 29 Fiddle Block Narrow with Tube Rivet Head & V-Jam Cleat
Star Price$27.95
Ronstan Series 29 Fiddle Block Narrow with Tube Rivet Head & V-Jam Cleat
MFG: RF187
Series 29 Fiddle Block - Narrow with Tube Rivet Head & V-Jam …
MFG: RF187
Star Price$27.95
Ronstan Series 20 Ball Bearing Block Single
Star Price$17.95
Ronstan Series 20 Ball Bearing Block Single
MFG: RF20100
Series 20 Ball Bearing Block - Single

Features:
  • Low friction
  • High static and …
MFG: RF20100
Star Price$17.95
Ronstan Series 20 Ball Bearing Block Single Loop Top
Star Price$9.95
Ronstan Series 20 Ball Bearing Block Single Loop Top
MFG: RF20101
Series 20 Ball Bearing Block - Single - Loop Top

Features:
  • Low …
MFG: RF20101
Star Price$9.95
Ronstan Series 20 Ball Bearing Block Single Loop Top Becket
Star Price$12.95
Ronstan Series 20 Ball Bearing Block Single Loop Top Becket
MFG: RF20111
Series 20 Ball Bearing Block - Single - Loop Top Becket

Features:
  • Low …
MFG: RF20111
Star Price$12.95
Ronstan Series 20 Ball Bearing Block Single Cheek
Star Price$13.95
Ronstan Series 20 Ball Bearing Block Single Cheek
MFG: RF20151
Series 20 Ball Bearing Block - Single - Cheek

Features:
  • Low friction
  • High …
MFG: RF20151
Star Price$13.95
Ronstan Series 20 Ball Bearing Block Single Cheek Rivet Mount
Star Price$17.95
Ronstan Series 20 Ball Bearing Block Single Cheek Rivet Mount
MFG: RF20151A
Series 20 Ball Bearing Block - Single - Cheek Rivet Mount

Features:
  • Low …
MFG: RF20151A
Star Price$17.95
Ronstan Series 20 Ball Bearing Block Upright Lead
Star Price$17.95
Ronstan Series 20 Ball Bearing Block Upright Lead
MFG: RF20171
Series 20 Ball Bearing Block - Upright Lead

Features:
  • Lead blocks are a low profile …
MFG: RF20171
Star Price$17.95
Ronstan Series 20 Ball Bearing Block Swivel Hook Head
Star Price$19.95
Ronstan Series 20 Ball Bearing Block Swivel Hook Head
MFG: RF20180
Series 20 Ball Bearing Block - Swivel Hook Head

Features:
  • Low friction
  • High …
MFG: RF20180
Star Price$19.95
Ronstan Series 20 Ball Bearing Block Double 2-Axis Shackle Head
Star Price$25.95
Ronstan Series 20 Ball Bearing Block Double 2-Axis Shackle Head
MFG: RF20202
Series 20 Ball Bearing Block - Double - 2-Axis Shackle Head

Features:
  • Low …
MFG: RF20202
Star Price$25.95
Ronstan Series 20 Ball Bearing Block Double Becket 2-Axis Shackle Head
Star Price$27.95
Ronstan Series 20 Ball Bearing Block Double Becket 2-Axis Shackle Head
MFG: RF20212
Series 20 Ball Bearing Block - Double - Becket - 2-Axis Shackle Head

Features:
  • Low …
MFG: RF20212
Star Price$27.95
Ronstan Series 20 ball Bearing Block Triple 2-Axis Shackle head
Star Price$34.95
Ronstan Series 20 ball Bearing Block Triple 2-Axis Shackle head
MFG: RF20302
Series 20 Ball Bearing Block - Triple - 2-Axis Shackle Head

Features:
  • Low …
MFG: RF20302
Star Price$34.95
Ronstan Series 20 Ball Bearing Block Triple Becket 2-Axis Shackle Head
Star Price$36.95
Ronstan Series 20 Ball Bearing Block Triple Becket 2-Axis Shackle Head
MFG: RF20312
Series 20 Ball Bearing Block - Triple - Becket - 2-Axis Shackle Head

Features:
  • Low …
MFG: RF20312
Star Price$36.95
Ronstan Series 20 Ball Bearing Block Triple Becket Cam Cleat 2-Axis Shackle Head
Star Price$72.95
Ronstan Series 20 Ball Bearing Block Triple Becket Cam Cleat 2-Axis Shackle Head
MFG: RF20332
Series 20 Ball Bearing Block - Triple - Becket - Cam Cleat - 2-Axis Shackle …
MFG: RF20332
Star Price$72.95
Ronstan Series 20 Ball Bearing Block Single Exit Cover Plate
Star Price$26.95
Ronstan Series 20 Ball Bearing Block Single Exit Cover Plate
MFG: RF20711
Series 20 Ball Bearing Block - Single - Exit Cover Plate

Features:
  • Precision molded …
MFG: RF20711
Star Price$26.95
Ronstan Series 20 Ball Bearing Orbit Block Single Dyneema Lashing Becket Option
Star Price$11.95
Ronstan Series 20 Ball Bearing Orbit Block Single Dyneema Lashing Becket Option
MFG: RF25109
Series 20 Ball Bearing Orbit Block - Single - Dyneema Lashing - Becket Option

The incredible Series 20 …
MFG: RF25109
Star Price$11.95
Ronstan Series 29 Block Single Loop Top
Star Price$9.95
Ronstan Series 29 Block Single Loop Top
MFG: RF280
Series 29 Block - Single - Loop Top

Features:
  • Maintenance …
MFG: RF280
Star Price$9.95
Ronstan Series 30 Ball Bearing Block Single Loop Top
Star Price$16.95
Ronstan Series 30 Ball Bearing Block Single Loop Top
MFG: RF30101
Series 30 Ball Bearing Block - Single - Loop Top

Features:
  • Low friction 2-stage ball …
MFG: RF30101
Star Price$16.95
Ronstan Series 30 Ball Bearing Orbit Block Single Becket Swivel Shackle Head
Star Price$18.95
Ronstan Series 30 Ball Bearing Orbit Block Single Becket Swivel Shackle Head
MFG: RF35100
Series 30 Ball Bearing Orbit Block™ - Single - Becket - Swivel Shackle Head

Ball Bearing Orbit …
MFG: RF35100
Star Price$18.95
Ronstan Series 30 Ball Bearing Orbit Block Single Becket Lashing head
Star Price$12.95
Ronstan Series 30 Ball Bearing Orbit Block Single Becket Lashing head
MFG: RF35101
Series 30 Ball Bearing Orbit Block™ - Single - Becket - Lashing Head

Ball Bearing Orbit …
MFG: RF35101
Star Price$12.95
Ronstan Series 30 Ball Bearing Orbit Block Stand Up Swivel
Star Price$23.95
Ronstan Series 30 Ball Bearing Orbit Block Stand Up Swivel
MFG: RF35140
Series 30 Ball Bearing Orbit Block™ - Stand Up Swivel

Ball Bearing Orbit Blocks™ boast the …
MFG: RF35140
Star Price$23.95
Ronstan Series 30 Ball Bearing Orbit Block Cheek
Star Price$14.95
Ronstan Series 30 Ball Bearing Orbit Block Cheek
MFG: RF35151
Series 30 Ball Bearing Orbit Block™ - Cheek

Ball Bearing Orbit Blocks™ boast the highest …
MFG: RF35151
Star Price$14.95
Ronstan Series 30 Ball Bearing Orbit Block Double
Star Price$30.95
Ronstan Series 30 Ball Bearing Orbit Block Double
MFG: RF35202
Series 30 Ball Bearing Orbit Block™ - Double

Ball Bearing Orbit Blocks™ boast the highest …
MFG: RF35202
Star Price$30.95
Ronstan Series 30 Ball Bearing Orbit Block Triple
Star Price$41.95
Ronstan Series 30 Ball Bearing Orbit Block Triple
MFG: RF35302
Series 30 Ball Bearing Orbit Block™ - Triple

Ball Bearing Orbit Blocks™ boast the highest …
MFG: RF35302
Star Price$41.95
Ronstan Series 30 Ball Bearing Orbit Block Triple Becket
Star Price$43.95
Ronstan Series 30 Ball Bearing Orbit Block Triple Becket
MFG: RF35312
Series 30 Ball Bearing Orbit Block™ - Triple - Becket

Ball Bearing Orbit Blocks™ boast the …
MFG: RF35312
Star Price$43.95
Ronstan Series 40 All Purpose Block Single Universal Head
Star Price$18.95
Ronstan Series 40 All Purpose Block Single Universal Head
MFG: RF41100
Series 40 All Purpose Block - Single - Universal Head

All purpose (AP) blocks are a great all around …
MFG: RF41100
Star Price$18.95
Ronstan Series 40 All Purpose Block Single Loop Top
Star Price$15.95
Ronstan Series 40 All Purpose Block Single Loop Top
MFG: RF41101
Series 40 All Purpose Block - Single - Loop Top

All purpose (AP) blocks are a great all around …
MFG: RF41101
Star Price$15.95
Ronstan Series 40 All Purpose Block Single Becket Universal Head
Star Price$25.95
Ronstan Series 40 All Purpose Block Single Becket Universal Head
MFG: RF41110
Series 40 All Purpose Block - Single - Becket - Universal Head

All purpose (AP) blocks are a great all …
MFG: RF41110
Star Price$25.95
Ronstan Series 40 All Purpose Block Single Becket Loop Top
Star Price$23.95
Ronstan Series 40 All Purpose Block Single Becket Loop Top
MFG: RF41111
Series 40 All Purpose Block - Single - Stand Up

All purpose (AP) blocks are a great all around …
MFG: RF41111
Star Price$23.95
Ronstan Series 40 All Purpose Block Single Stand Up
Star Price$27.95
Ronstan Series 40 All Purpose Block Single Stand Up
MFG: RF41140
Series 40 All Purpose Block - Single - Stand Up

All purpose (AP) blocks are a great all around …
MFG: RF41140
Star Price$27.95
Ronstan Series 40 All Purpose Block Single Cheek
Star Price$27.95
Ronstan Series 40 All Purpose Block Single Cheek
MFG: RF41151
Series 40 All Purpose Block - Single - Cheek

All purpose (AP) blocks are a great all around solution. …
MFG: RF41151
Star Price$27.95
Ronstan Series 40 Ball Bearing Block Single Universal Head
Star Price$24.95
Ronstan Series 40 Ball Bearing Block Single Universal Head
MFG: RF40100
Series 40 Ball Bearing Block - Single - Universal Head

Sheaves running on Acetal or Torlon® ball …
MFG: RF40100
Star Price$24.95
Ronstan Series 40 Ball Bearing Block Single Stand Up
Star Price$32.95
Ronstan Series 40 Ball Bearing Block Single Stand Up
MFG: RF40140
Series 40 Ball Bearing Block - Single - Stand Up

Sheaves running on Acetal or Torlon® ball bearings …
MFG: RF40140
Star Price$32.95
Ronstan Series 45 Core Block Single Swivel Shackle Head
Star Price$45.95
Ronstan Series 45 Core Block Single Swivel Shackle Head
MFG: RF44100
Series 45 Core Block™ - Single - Swivel Shackle Head

Core Blocks™ are a true all round …
MFG: RF44100
Star Price$45.95
Ronstan Series 40 Ball Bearing Orbit Block Single Becket Swivel Head
Star Price$25.95
Ronstan Series 40 Ball Bearing Orbit Block Single Becket Swivel Head
MFG: RF45110
Series 40 Ball Bearing Orbit Block™ - Single - Becket - Swivel Head

Core Blocks™ are a true …
MFG: RF45110
Star Price$25.95
Ronstan Nylatron Sheave Box Single Upright Lead Block
Star Price$18.95
Ronstan Nylatron Sheave Box Single Upright Lead Block
MFG: RF453
Nylatron Sheave Box - Single Upright Lead Block

Lead blocks are a low profile solution for leading …
MFG: RF453
Star Price$18.95
Ronstan Series 40 Ratchet Orbit Block Single Auto Swivel Shackle Head
Star Price$54.95
Ronstan Series 40 Ratchet Orbit Block Single Auto Swivel Shackle Head
MFG: RF46100
Series 40 Ratchet Orbit Block™ - Single - Auto - Swivel Shackle Head

Automatic …
MFG: RF46100
Star Price$54.95
Ronstan Series 29 Utility Block Single Ferrule Eye Head
Star Price$14.95
Ronstan Series 29 Utility Block Single Ferrule Eye Head
MFG: RF469
Series 29 Utility Block - Single - Ferrule Eye Head

Stainless steel cheeks and Acetal sheaves ensure a …
MFG: RF469
Star Price$14.95
Ronstan Series 50 High Load Block Single Universal Head
Star Price$51.95
Ronstan Series 50 High Load Block Single Universal Head
MFG: RF50100HL
Series 50 High Load Block - Single - Universal Head

Ideal for high load applications. Wear resistant …
MFG: RF50100HL
Star Price$51.95
Ronstan Series 50 All Purpose Block Single Universal Head
Star Price$27.95
Ronstan Series 50 All Purpose Block Single Universal Head
MFG: RF51100
Series 50 All Purpose Block - Single - Universal Head

All purpose (AP) blocks are a great all around …
MFG: RF51100
Star Price$27.95
Ronstan Series 50 All Purpose Block Single Loop Head
Star Price$26.95
Ronstan Series 50 All Purpose Block Single Loop Head
MFG: RF51101
Series 50 All Purpose Block - Single - Loop Head

All purpose (AP) blocks are a great all around …
MFG: RF51101
Star Price$26.95
Ronstan Series 50 All Purpose Block Single Becket Universal Head
Star Price$38.95
Ronstan Series 50 All Purpose Block Single Becket Universal Head
MFG: RF51110
Series 50 All Purpose Block - Single - Becket - Universal Head

All purpose (AP) blocks are a great all …
MFG: RF51110
Star Price$38.95
Ronstan Series 55 Ball Bearing Orbit Block Single Becket Swivel Head
Star Price$37.95
Ronstan Series 55 Ball Bearing Orbit Block Single Becket Swivel Head
MFG: RF55110
Series 55 Ball Bearing Orbit Block™ - Single - Becket - Swivel …
MFG: RF55110
Star Price$37.95
Ronstan Series 55 Ratchet Orbit Block Single Swivel Head Auto & Manual
Star Price$69.95
Ronstan Series 55 Ratchet Orbit Block Single Swivel Head Auto & Manual
MFG: RF56100
Series 55 Ratchet Orbit Block™ - Single - Swivel Head - Auto & Manual

Automatic Ratchet …
MFG: RF56100
Star Price$69.95
Ronstan Series 25 Utility Block Single Loop Head
Star Price$9.95
Ronstan Series 25 Utility Block Single Loop Head
MFG: RF571
Series 25 Utility Block™ - Single - Loop Head

Stainless steel cheeks and Acetal sheaves ensure a …
MFG: RF571
Star Price$9.95
Ronstan Series 25 Utility Block Single Swivel Shackle Head
Star Price$15.95
Ronstan Series 25 Utility Block Single Swivel Shackle Head
MFG: RF573
Series 25 Utility Block™ - Single - Swivel Shackle Head


Stainless steel cheeks and Acetal …
MFG: RF573
Star Price$15.95
Ronstan Series 60 Core Block Single
Star Price$72.95
Ronstan Series 60 Core Block Single
MFG: RF64100
Series 60 Core Block™ - Single

Core Blocks™ are a true all round solution. A tuned 2-stage …
MFG: RF64100
Star Price$72.95
Ronstan Series 60 Core Block Single Becket
Star Price$67.95
Ronstan Series 60 Core Block Single Becket
MFG: RF64110
Series 60 Core Block™ - Single - Becket

Core Blocks™ are a true all round solution. A tuned …
MFG: RF64110
Star Price$67.95
Ronstan Series 19 Utility Block Single Tube Rivet
Star Price$9.95
Ronstan Series 19 Utility Block Single Tube Rivet
MFG: RF661
Series 19 Utility Block™ - Single - Tube Rivet

Stainless steel cheeks and Acetal sheaves ensure a …
MFG: RF661
Star Price$9.95
Ronstan Series 19 Utility Block Single Ferrule Eye Head
Star Price$15.95
Ronstan Series 19 Utility Block Single Ferrule Eye Head
MFG: RF663
Series 19 Utility Block™ - Single - Ferrule Eye Head

Stainless steel cheeks and Acetal sheaves …
MFG: RF663
Star Price$15.95
Ronstan Series 75 Core Block Single
Star Price$97.95
Ronstan Series 75 Core Block Single
MFG: RF74100
Series 75 Core Block™ - Single

Core Blocks™ are a true all round solution. A tuned 2-stage …
MFG: RF74100
Star Price$97.95
Ronstan Snatch Block Acetal Sheave Single 11mm(7/16") Max. Rope Diameter
Star Price$122.95
Ronstan Snatch Block Acetal Sheave Single 11mm(7/16") Max. Rope Diameter
MFG: RF6710
Snatch Block Acetal Sheave - Single - 11mm(7/16") Max. Rope Diameter

Snatch blocks are a tough and …
MFG: RF6710
Star Price$122.95
Ronstan Snatch Block Acetal Sheave Single 12mm(1/2") Max. Rope Diameter
Star Price$168.95
Ronstan Snatch Block Acetal Sheave Single 12mm(1/2") Max. Rope Diameter
MFG: RF6720
Snatch Block Acetal Sheave - Single - 12mm(1/2") Max. Rope Diameter

Snatch blocks are a tough and …
MFG: RF6720
Star Price$168.95
Ronstan Snatch Block Alloy Sheave 16mm(5/8") Max. Rope Diameter
Star Price$177.95
Ronstan Snatch Block Alloy Sheave 16mm(5/8") Max. Rope Diameter
MFG: RF6730
Snatch Block Acetal Sheave - Single - 16mm(5/8") Max. Rope Diameter

Snatch blocks are a tough and …
MFG: RF6730
Star Price$177.95
Ronstan Single Lead Block 19mm(3/4") Sheave Diameter
Star Price$11.95
Ronstan Single Lead Block 19mm(3/4") Sheave Diameter
MFG: RF917
Single Lead Block - 19mm(3/4") Sheave Diameter

Lead blocks are a low profile solution for leading …
MFG: RF917
Star Price$11.95
Ronstan Single Lead Block 29mm(1-3/32") Sheave Diameter
Star Price$14.95
Ronstan Single Lead Block 29mm(1-3/32") Sheave Diameter
MFG: RF919
Single Lead Block - 29mm(1-3/32") Sheave Diameter

Lead blocks are a low profile solution for leading …
MFG: RF919
Star Price$14.95

Write A New Review

Ronstan Series 75 Core Block Single Aluminum Rope/Wire Sheave has not been reviewed yet. Review Now.
Series 75 Core Block - Single - Aluminum Rope/Wire Sheave

Core Blocks are a true all round solution. A tuned 2-stage bearing system provides excellent performance across the full working load range with an integrated thrust bearing feature and the resilience to handle high dynamic or static loads. Acetal sheave, alloy cheeks and stainless fixings complete the durable package. For reliability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.

Universal Bearing
Dynamic and high static load performance

The Ronstan Universal Bearing incorporates our proven 2-stage bearing system

Stage 1 - Under moderate loads, Acetal ball bearings ensure minimum friction.

Stage 2 - Under heavy loads, where deformation of ball bearings alone would result in increased friction, a sliding Acetal bearing on a polished stainless steel race takes over, maintaining low friction performance.

Additionally the ball bearings are configured to act as a thrust bearing between the sheave and cheeks, preventing the sheave from rubbing on the cheeks and causing friction when the line lead in and out of the block isn't perfect. Particularly important for cheek blocks.

Alloy Cheek Plates
Block cheeks are manufactured from the highest quality alloy for maximum strength. Material optimisation and the cut-away design minimises weight and allows easy fresh water rinsing of salt and debris from the bearings. Cheek design has been further styled with flaring at the block throat and reduced gap between the cheek and sheave, minimising rope wear.

Universal head
The head assembly incorporates a brass bearing washer to provide smooth 360™ rotation of the post and shackle. A set screw arrangement allows the head to be locked at 0™ or 90™.

Shackles are high quality forged grade 316 stainless steel.

Features:
  • Class leading performance and sleek, contemporary styling
  • Excellent dynamic and high static load performance
  • Less than half the friction of the nearest competitor
  • Universal head with full 3-axis articulation
  • Head posts can be locked at 0 or 90 degrees, by using a 2.5mm Hex/Allen Key
  • Central hub hole can be used as a becket take-off or tie-up point
  • Durable alloy Rope/Wire sheave


Applications:
  • Ideal for mainsheet, halyard and spinnaker sheet applications on boats to 14M (46')
  • Various control line applications on larger yachts
  • Aluminium sheave which has a deep groove profile specifically made for use with wire


Materials:
  • Sheave: U.V. stabilized Acetal
  • Cheek body: Aluminium Alloy
  • Ball Bearings: High compression strength carbon black Acetal
  • Shackle, head post & hub: Grade 316 stainless steel


Specifications:
Sheave Ø:75mm(3")
Max. Rope Ø:14mm(9/16")
Max. Cable Ø: 8mm(5/16")
Pin Ø:8mm(5/16")
M.W.L.:1,500kg(3,300lbs)
B. L.:3,000kg(6,600lbs)
Weight:432g(15.3oz)

Write A New Review

Ronstan Series 75 Core Block Single Aluminum Rope/Wire Sheave has not been reviewed yet. Review Now.

Ronstan Marine Top Sellers