40MM SINGLE BLOCK

A20401S – 40mm Dynamic Single Ultra-Strap Block | High-Performance Block for Keelboats & Dinghies

The A20401S 40mm Dynamic Single Ultra-Strap Block is built from high-strength, lightweight glass-loaded nylon and combines Allen's renowned dynamic bearing technology to deliver a high-performance block perfectly suited for keelboats and dinghies.

Ideal for use on main, jib and spinnaker sheets on dinghies, as well as keelboat control lines, the A20401S is a particularly strong choice for dinghy jib and mainsheet systems.

Patented Bearing System – Dynamic Block Technology Dynamic Blocks feature an exclusive patented bearing system using twin rows of stainless-steel ball bearings running on a stainless-steel rail. The ball bearings are caged for further friction reduction, delivering superior load-carrying capacity and outstanding longevity compared to conventional bearing systems on the market.

Patented Ultra-Strap – Stronger, More Durable & Rope-Friendly The patented Ultra-Strap is used across Allen's 20, 30 and 40mm Dynamic block range. What sets it apart from other designs is its unique coining process, which strengthens the strap for increased reliability and durability, while also making it rope-friendly to protect your lines during use.

Please note: The image shown is of the A20401SR removable Ultra-Strap block. This version, the A20401S, features a fixed riveted strap through the centre rather than a bolted removable strap.

Becket – Versatile Tie-Off Point The 40mm range features a large central hole that doubles as a becket tie-off point. Specific becket variations are also available for dedicated applications