Seldén ball bearing (BBB) blocks for dinghies, covering the BBB20, BBB25 high load, BBB30, BBB40 and BBB60 ranges in single, double, triple and fiddle configurations with a full choice of attachment, becket and cam cleat options.
How to choose
Ball bearing blocks (BBB) use stainless steel ball bearings to minimise friction under dynamic loads, making them the correct choice wherever a line runs frequently: mainsheets, spinnaker sheets, control lines and purchase systems. For slow-moving or static loads such as boom vangs and halyard tuning, a plain bearing block is the more practical option and is covered in a separate collection.
Start with sheave size, which follows line diameter. The BBB20 suits lines up to 6 mm for light control lines on smaller dinghies. The BBB30 suits lines up to 8 mm for mid-weight mainsheets and control lines. The BBB40 and BBB60 both suit lines up to 10 mm for heavier mainsheet and spinnaker applications on two-handed dinghies and keelboats. The BBB25 high load range is a specialist option with all-stainless construction rated for wire and rope up to 5 mm, suited to compact, high-load halyard and tackle systems.
Then choose sheave count. A single block redirects a line. A double provides 2:1 purchase in a tackle. A triple provides 3:1 or higher. A fiddle block, available in the BBB40 and BBB60 ranges, combines a large and small sheave in a single body, giving a built-in purchase system in a compact unit that avoids the need for two separate blocks.
Finally choose attachment and variant. Swivel blocks suit variable lead angles and lock at 0° or 90°. Strap and fixed-eye blocks suit fixed attachment points. Tie-on blocks lash directly to a fitting point, saving weight. Cheek blocks mount flush to the deck. Add a becket when the standing end of a purchase system anchors to the block. Add a cam cleat variant to lock the line without a separate cleat. Heavy duty BBB60 versions use stainless ball bearing races for higher sustained loads.
What's in this collection
The BBB20 range covers lines up to 6 mm with singles in strap, becket, shackle, tie-on, lead, cheek and through-deck lead versions, plus doubles (standard and becket) and triples (standard, becket, cam and becket cam).
The BBB25 high load range covers wire and rope up to 5 mm with all-stainless construction. Singles are available with strap loop, fixed pin, removable pin and becket removable pin. Doubles and triples are available with and without becket.
The BBB30 range covers lines up to 8 mm with singles in swivel, strap, becket, tie-on, cheek, stand-up eyestrap and clew/stainless ring versions, plus doubles (standard and becket) and triples (standard, becket, cam and becket cam).
The BBB40 range covers lines up to 10 mm. Singles are available in swivel, strap, becket strap, tie-on and cheek versions with cam cleat options on swivel variants. Doubles come in standard and becket versions. Triples add swivel and cam cleat combinations. Fiddle blocks are available as standard, becket, cam, becket cam, and a hook cam eye variant where the hook allows quick attachment and the eye on the cam arm serves as a cascade dead-end. The linked BBB30/BBB40 block combines 40 mm and 30 mm sheaves in one unit.
The BBB60 range covers lines up to 10 mm with Delrin ball bearings. Singles come in swivel, swivel becket, swivel cam, swivel becket cam and tie-on versions, with standard and heavy duty variants on swivel and tie-on types. Doubles come in swivel. Triples cover swivel, swivel becket, swivel cam and swivel becket cam. Fiddle blocks mirror the triple range. Cheek flat base blocks, standard and heavy duty, mount to deck or coaming surfaces.
