How to choose
A triple block carries three sheaves, making it the right choice for higher load purchase systems where load is significant and mechanical advantage is needed over a long range of movement. Common applications are mainsheet systems, kickers, vangs, rig tension systems and cascade arrangements.
Choose sheave size to match your line diameter. BBB20 triple blocks suit lines up to 6 mm, typically light control lines on smaller dinghies. BBB30 triples suit lines up to 8 mm for mid-sized dinghy systems. BBB40 and BBB60 triples both suit lines up to 10 mm for heavier mainsheet and tackle applications on larger dinghies and keelboats. The BBB25 high load triple is a specialist option with all-stainless construction rated for wire and rope up to 5 mm. Suited to compact, high-load tackle systems on smaller boats.
The becket variant adds a fixed attachment point on the block body for anchoring the standing end of a purchase system. You need a becket when the triple block forms the moving part of a tackle and the standing end returns to the block itself.
The cam cleat variant integrates a cleat directly into the block, so the line can be locked off without a separate cleat fitting. BBB20 and BBB30 cam variants use a size 27 cam cleat with top-guide. BBB40 cam variants also use a 27 mm composite cam cleat with an adjustable arm angle. BBB60 cam variants step up to a 38 mm composite cam cleat, also with adjustable arm and the eye on the cam cleat arm can serve as a dead-end for a cascade system. Note that adding a cam cleat reduces the safe working load of the overall assembly compared to the block alone, so check the individual product specification if load is close to the limit.
The BBB40 and BBB60 ranges feature a swivel shackle that locks at 0° or 90°, suited to applications where the lead angle varies. The BBB20, BBB25 and BBB30 ranges use a fixed attachment.
What's in this collection
The BBB20 ball bearing triples cover lines up to 6 mm and are available in four variants: standard (402-101-05R), becket (402-101-06R), cam (402-101-07R) and becket cam (402-101-08R). The standard and becket cam versions are specifically referenced for 420 class rig tension systems.
The BBB25 high load triples cover wire and rope up to 5 mm with all-stainless construction and ball cages. Available as a strap triple (402-201-10R) and a becket strap triple (402-201-11R).
The BBB30 ball bearing triples cover lines up to 8 mm with a stainless attachment eye and glass fibre reinforced polyamide sheaves. Available as standard (403-101-06R), becket (403-101-10R), cam with size 27 top-guide cleat (403-101-11R) and becket cam (403-101-07R).
The BBB40 ball bearing triples cover lines up to 10 mm with a swivel shackle locking at 0° or 90°. Available as swivel (404-101-08R), swivel becket (404-101-09R), swivel cam with 27 mm composite cleat (404-101-10R) and swivel becket cam (404-101-11R).
The BBB60 ball bearing triples cover lines up to 10 mm with Delrin ball bearings and a swivel shackle locking at 0° or 90°. Available as swivel (406-601-06R), swivel becket (406-601-07R), swivel cam with 38 mm composite cleat (406-601-08R) and swivel becket cam (406-601-09R). The cam cleat arm eye on cam variants can be used as a dead-end for cascade rigging.
Dinghy class applications
The 420 is specifically referenced in this collection. The BBB20 standard triple (402-101-05R) and BBB20 becket cam triple (402-101-08R) are both cited as suitable for 420 rig tension systems, where a compact, low-friction triple block is needed in the jib halyard tension purchase.
