Single Blocks

Buy Seldén single blocks for your sailing yacht. Ball bearing, plain bearing and roller bearing blocks in all sizes. From BBB 20 to PBB 100, for lines from 2 to 16 mm.

Products in Single Blocks

84 products found

Seldén BBB 20 Trapeze Block

Seldén BBB 20 Trapeze Block

Seldén BBB 20 trapeze block with ball bearing and a safe working load of 150 kg. Suitable for lines of Ø2–6 mm, specifically designed for trapeze systems on dinghies.

€ 52,09
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Seldén RBB 60 Single Block

Seldén RBB 60 Single Block

Seldén RBB 60 single block with roller bearing for maximum performance and a safe working load of 2500 kg. Suitable for lines of Ø8–12 mm, weighing only 350 g.

€ 369,59
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Seldén S 40+ Single Block tie-on

Seldén S 40+ Single Block tie-on

Seldén S 40+ single block with soft line attachment, ball bearing and a safe working load of 350 kg. Suitable for lines of Ø6–10 mm, ideal as a sheet block or trimming block on sailboats.

€ 67,19
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Seldén PBB 70 Single Block

Seldén PBB 70 Single Block

Seldén PBB 70 single block with plain bearing and D-shackle, suitable for lines Ø10–14 mm. Safe working load 1500 kg, breaking strength 3000 kg, with toggle button.

€ 67,19
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Seldén BBB 60 Single Block

Seldén BBB 60 Single Block

Seldén BBB 60 single block with ball bearing and D-shackle, suitable for lines Ø6–10 mm. Safe working load 350 kg, breaking strength 1000 kg, weight 118 grams.

€ 54,50
In stock
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Looking to buy single blocks for your sailing yacht? At 123Furling you will find an extensive range of single blocks from leading manufacturers. A single block is the most fundamental type of sailing block. With one sheave, it is ideal for redirecting lines, as part of a simple purchase system or as a standalone block for light to medium-duty applications.

What are single blocks used for?

Single blocks are the most versatile blocks on board any sailing yacht. They are used for redirecting sheets, halyards, trim lines and control lines. Wherever a line needs to change direction, a single block provides the solution. Their compact design and low weight mean they can be mounted at virtually any position on board.

Combined with a second block, a single block forms a simple 2:1 purchase system. This doubles the pulling force and makes it possible to handle heavier sails with less effort. Single blocks are also widely used as turning blocks on the cockpit floor, at the mast or on deck.

Which type of single block suits your application?

Choosing the right single block depends on several factors: the expected load, line diameter, preferred bearing type and mounting method. Below you will find an overview of the available types.

Ball bearing single blocks (BBB series) are the most popular choice for most applications. The stainless steel ball bearings ensure minimal friction and smooth operation, both at low and high loads. Available in sizes from 20 mm to 60 mm, suitable for lines from 2 to 10 mm.

Plain bearing single blocks (PBB series) offer excellent performance under high, constant loads. The plain bearing is exceptionally strong and durable, making these blocks ideal for larger yachts with thicker lines. Available for lines from 8 to 16 mm.

Roller bearing single blocks (RBB series) combine the smooth operation of ball bearings with the load capacity of roller bearings. These are premium blocks for the heaviest applications, such as large sheets and halyards.

Tie-on single blocks (S series) are attached with a Dyneema loop instead of a D-shackle. This results in the lowest weight and makes them popular with racing sailors and weight-conscious cruisers.

Mounting variants

Within each series, single blocks are available in different mounting variants to suit your specific situation:

  • With D-shackle: the most common variant, quick to mount and versatile for any position
  • Fixed model: for permanent attachment points where the block does not need to rotate
  • Swivel model: the block automatically follows the line direction, preventing wear
  • With becket: an additional attachment point for starting a purchase system
  • With cam cleat: integrated cleat for immediate line cleating after trimming
  • Through-deck mounting: installed through the deck for a clean and permanent solution
  • Tie-on attachment: minimal weight using a Dyneema loop instead of metal hardware

Choosing the right single block

When selecting a single block, it is important to consider the safe working load (SWL) and breaking strength. The SWL indicates how much force the block can safely handle during normal use. The breaking strength is the maximum force before the block fails, typically twice the SWL. Always choose a block with an SWL well above your expected load.

Line diameter is a second important criterion. Each block is designed for a specific range of line diameters. A line that is too thin may jam, while a line that is too thick will not fit through the sheave. Always check the specifications for the correct line diameter.

Why buy single blocks at 123Furling?

  • Extensive range from leading brands in all sizes and variants
  • Ball bearing, plain bearing, roller bearing and tie-on models
  • Safe working loads from 200 kg to 2000 kg
  • Suitable for lines from 1 mm to 16 mm
  • Competitive prices and fast delivery throughout Europe
  • Personal advice from experienced sailors

Need help?

Not sure which single block best suits your boat and application? Feel free to contact us. Our advisors are happy to help you find the right block for your situation.

Need help?

Our experts are happy to help you choose the right system.

info@123furling.com
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