Ronstan Series 20 Ball Bearing Double Block with Becket and Shackle has sheaves that are 20mm in diameter and a dual axis head that allows the block to be fixed in either plane depending on application.
Features
Two-way head - can be fixed at 0 or 90 degrees
Low friction, high performance, fiber reinforced polyamide sheave and cheeks, with precision moulded, UV stabilized Acetal sheaves running on stainless steel ball
Grade 316 stainless steel load strap and head fitting
High static and dynamic load capacity
Lightweight and durable
Specifications
Pin diameter: 5/32 in. (4mm)
Maximum rope diameter: 1/4 in. (6mm)
Maximum working load: 770 lbs.
Sheave diameter: 3/4 in.
Breaking load: 1540 lbs.
Weight: 1.6 oz.
Ronstan Series 20 Ball Bearing Triple Block with Shackle Triple Ball Bearing block has sheaves that are 20mm in diameter. Ideal for powerful purchase systems on dinghy vangs, rig tensioning systems on skiffs, etc.
Features
Two-way head - can be fixed at 0 or 90 degrees
Low friction, high performance, fiber reinforced polyamide sheave and cheeks, with precision moulded, UV stabilized Acetal sheaves running on stainless steel ball
Grade 316 stainless steel load strap and head fitting
High static and dynamic load capacity
Lightweight and durable
Specifications
Pin diameter: 5/32 in. (4mm)
Maximum rope diameter: 1/4 in. (6mm)
Maximum working load: 880 lbs.
Sheave diameter: 3/4 in.
Breaking load: 1870 lbs.
Weight: 2.2 oz.
The Series 20 Ball Bearing Triple Block with Becket, Cleat and Shackle has a 2-way head that can be fixed at 0 or 90 degrees. It provides powerful, efficient adjustment and secure holding for important lines under load.
Typical applications
Mainsheet Systems: the triple block's three sheaves enable multi-part tackle (such as a 6:1 or 7:1 purchase) for the mainsheet, enabling easier and finer trimming of the mainsail, especially under heavy load.
Boom Vangs: provides similar purchase to control boom height and leech tension, crucial for sail shape and performance.
Backstay Adjusters: backstay systems may use such blocks to quickly adjust mast bend or forestay tension.
Component functions
Triple Sheaves: multiply pulling force and reducing the manual effort needed for control.
Becket: serves as an anchor point for the end of the control line, providing a starting/ending reference for the tackle setup.
Cleat: Integrated cam cleat allows locking off the line at any point, holding the adjustment hands-free.
Shackle: Provides a secure, detachable connection to a fixed point like a boom bale, traveler, deck padeye, or other fitting.
Specifications
Maximum rope diameter: 1/4 in. (6mm)
Maximum working load: 880 lbs.
Sheave diameter: 3/4 in.
Breaking load: 1870 lbs.
Weight: 4.3 oz.
Pin diameter: 5/32 in. (4mm)
The Ronstan Series 20 Ball Bearing Single Block with Becket and Loop Top suits a variety of attachment methods. Can be fitted with a shackle in either of two planes to allow correct alignment of the block.
Features
Low friction, high performance, fiber reinforced polyamide sheave and cheeks, with precision moulded, UV stabilized Acetal sheaves running on stainless steel ball
High static and dynamic load capacity
Lightweight and durable
Grade 316 stainless steel load strap and head fitting
Specifications
Maximum rope diameter: 1/4 in. (6mm)
Maximum working load: 550 lbs.
Sheave diameter: 3/4 in.
Breaking load: 1210 lbs.
Weight: 0.6 oz.
The Ronstan Series 20 Cheek Block is ideal for control lines and vangs, Cunninghams and traveller controls on dinghys, sailing canoes, and other small boats.
Features
Low friction, high performance, fiber reinforced polyamide sheave and cheeks, with precision moulded, UV stabilized Acetal sheaves running on stainless steel ball bearings
High static and dynamic load capacity
Lightweight and durable
Double through-bolt mounting for maximum load capacity.
Specifications
Maximum rope diameter: 1/4 in. (6mm)
Maximum working load: 550 lbs.
Sheave diameter: 3/4 in.
Breaking load: 1210 lbs.
Weight: 0.5 oz.
Fastener diameter: 5/32 in. (4mm)
Ronstan designs and manufactures world-class blocks and pulleys for all types of sailing. The Series 20 uses 20mm ball bearing sheaves and fits 6mm or 1/4" line.
Features
Low friction, high performance, fiber reinforced polyamide sheave and cheeks, with precision moulded, UV stabilized Acetal sheaves running on stainless steel ball
Grade 316 stainless steel load strap and head fitting
High static and dynamic load capacity
Lightweight and durable
Specifications
Pin diameter: 1/8 in. (3mm)
Maximum rope diameter: 1/4 in. (6mm)
Maximum working load: 550 lbs.
Sheave diameter: 3/4 in.
Breaking load: 1210 lbs.
Weight: 0.7 oz.
The Ronstan Series 20 Ball Bearing Single Block with Hook is ideal for connecting webbing loops on sails, including Cunningham and outhaul attachments.
Features
Low friction, high performance, fiber reinforced polyamide sheave and cheeks, with precision moulded, UV stabilized Acetal sheaves running on stainless steel ball
High static and dynamic load capacity
Lightweight and durable
Low profile hook swivels for quick and easy attachment
Stainless steel hook suits rope, webbing and hard attachments
Grade 316 stainless steel load strap and head fitting
Specifications
Maximum rope diameter: 1/4 in. (6mm)
Maximum working load: 220 lbs.
Sheave diameter: 3/4 in.
Breaking load: 440 lbs.
Weight: 0.7 oz.
Lead blocks are a low profile solution for leading halyards or other rig sail controls back to cleats or jammers. Precision moulded Acetal sheaves running on stainless steel or Torlon® ball bearings provide high performance & low friction.
Ronstan designs and manufactures world-class blocks and pulleys for all types of sailing. The Series 20 uses 20mm ball bearing sheaves and fits 6mm or 1/4" line.
Features
Compatible with our in-house custom risers
Can be mounted side by side for multiple lines
Tip: use our custom riser to color code each lead block location
Specifications
Maximum working load: 500 lbs. or 250 kg.
Breaking load: 1210 lbs. or 550 kg.
Weight: 18g
Ronstan's Series 20 fits 6mm or 1/4" line. These high performance blocks use 20mm sheaves and are engineered to achieve excellent strength-to-weight ratios and a long, maintenance free service life.
