Allen sheave boxes are available with either plain or ball bearings, a choice of sheave material, Acetal resin, pressure die cast high grade aluminium or high load stainless steel.
They are suitable for all types of halyard systems, control line systems and general running rigging.
The low profile range feature Allen's unique hook-in cage designed to deal with high loads of modern rigs.
The A4808 high tension sheave block features a twist open facility for better access when changing halyards etc