A sailboat block consists of one or more sheaves held between two cheeks or chocks. It increases mechanical advantage and can be used to alter the direction of lines running through it.
These devices have multiple uses on board including mainsail block and tackle, spinnaker sheet guide, barber hauler, hell block, deck block and downhaul tackle, among others.
The great majority of cruising sailboat blocks are aluminum or stainless steel. Titanium blocks now can be found on some racing boats, while traditional craft have beautiful wooden blocks. Single, double and even triple blocks are used in block and tackle to increase mechanical advantage, as on a mainsail sheet.
Blocks can be attached via a becket, a swivel, a rotating tower with a jam or cam cleat, a fork, a fabric strop or be screwed to the deck or attached to another fitting. Blocks with narrow metal sheaves are used with cable or wire rope. Sheaves can ride on ball bearings, rollers or a simple friction axle. Ratchet blocks have internal teeth so that the sheave turns in one direction only, making it easier to keep tension on the line.
Choice will depend on specific application, line diameter and the possible need for an integrated cleat. Blocks with rollers are generally the most efficient due to reduced friction and increased sturdiness.
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Sailboat double block with swivel / becket (max. rope ø : 10 mm) 94206 Wichard
Commentary Complete range of blocks Excellent high-speed low load and high-function load characteristics Interchangeable head fastening systems for multiple attachment...
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Single flat cheek block for sailboats (max. rope ø : 6 mm) PBB 60 - SWL = 1500 KG Seldén
HIGH LOAD PBB These blocks are optimised for wires or Dyneema®/Spectra® core. TECHNICAL FEATURES Stainless steel, electro polished...
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Sailboat single lashing block (max. rope ø : 14 mm) 2 T | KB14 Karver Systems
SIMPLICITY AND DESIGN Simple, reliable and efficient - the Karver KB block combines both freedom of attachment and extreme safety LIGHT WEIGHT Compared to traditional blocks (at equal working...
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Sailboat double block with swivel (max. rope ø : 12 mm) 01476-25 Eval
STAINLESS STEEL BLOCKS WITH DOUBLE WHEELS AND SWIVEL Code 1476-25 , Dimensions mm L...
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Sailboat double block with swivel (max. rope ø : 16 mm) 3248 Harken
Sheave Ø (mm)100 mm Sheave Ø (in)3 15/16...
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Sailboat triple block with swivel (max. line ø : 12 mm) RF70300 - M.W.L - 1250 kg Ronstan
Low friction, 2-stage ball bearing system High static...
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Sailboat triple block with swivel (max. line ø : 10 mm) HT 92061 Holt
ORGANIC BEARING SYSTEM Aluminium large central axle provides a lightweight alternative to the stainless....
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Sailboat halyard lift single block OFFSHORE Bainbridge international
Designed for offshore applications including Volvo, BT Global Challenge and performance...
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Sailboat single block for stanchion WL/2 Spinlock
Compact Stanchoin Lead System Features and Benefits - Safe, compact design - Reduces furling line friction -...
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Fiddle block with swivel / becket for sailboats (max. line ø : 14 mm) A2044 Allen Brothers
A2044 40mm Dynamic Block Swivel with 20mm fiddle block and becket The 40mm dynamic bearing block is an essential piece of equipment...
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Fiddle block with swivel for sailboats (max. line ø : 14 mm) BL = 3800 KG Rutgerson
The Rutgerson block assortment is unique in its design and functionality. The key to its success is that both the sheave and the cheeks are produced from a high-tech composite material of such a great strength that no stainless steel reinforcement is needed....
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Wood and bronze block for classic sailboats Solimar
Simple,double and triple blocks,with and without becket,fieddle...
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Sailboat single block with swivel 60 - SWL = 800 KG Antal
New by Antal the One Piece Frame block, the block without pins or screws, it is a light and strong solution: simply a hard black anodized and...
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Sailboat double block with swivel (max. rope ø : 30 mm) Hi-MOD Petersen Stainless
The Hi-MOD Marine Blocks are a simple and durable cruising block which work well under heavy loads and are less prone to jamming . Made...
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Sailboat double block with fixed head Equiplite Europe
Equiplite™ Dual Sheave Block use DSK 75 ULTRA loops to take the loads directly through the centre of the sheave. This allows the blocks to be extremely...
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Sailboat double block with shackle / becket 19.84 Sea Sure
19mm carbon fibre cheeked ball race blocks Light weight, high load carrying capacity blocks Reliable race proven designs High wear resistant cheek material extends life if miss-lead occurs Freewheeling...
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Advantages: •easily running ball bearing stainless steel •bearing shell and balls of stainless steel •wobble riveting:...
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Sailboat stainless steel single block Rondal
Elegantly designed, and constructed from high-gloss stainless steel 316 with black anodised and Teflon-sealed sheaves, Rondal blocks combine elegance and efficiency with...
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Single flat cheek block with jamming cam for sailboats (max. rope ø : 16 mm) 82999 Barton Marine
High Load Blocks manufactured from marine grade aluminium and 'Spectro' grey anodised for high UV stability and durability. Sheaves are precision urned from...
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Sailboat double friction block with lashing (max. rope ø : 7 mm) CSS242 Colligo Marine
Enhanced Double Lashing Block, 7 mm, Black Price: US$69.00 Ask a question about this product Our Patent Pending, Enhanced Double...
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Block for classic sailboats 2FA200S - SWL 1400 La Nantaise de Poulies
Fonctionnalities Simple Hand Strap Optional Becket Optional Rope Specifications Force II blocks are made in order to join together the design features and the highest esthetics...
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Double block for classic sailboats Dryade
Dryade blocks are made in a wide variety of sizes accepting sheaves of diameters from 30 to 160 mm in the standard series. The technical and marine shells,...
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Sailboat double block with shackle / becket S315 SINOX INTERNATIONAL
Field of application Mame blocks are specifically...
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Our High Performance blocks are developed with emphasis on design and strength. The blocks have aluminium ball...
