The Allen Low Profile Aluminium Sheave Box - Ball Bearing is a versatile and durable option for attaching to your mast or boom. Made from cast aluminium, it offers a choice of two sheave materials and is compatible with a wide range of sizes and applications. The lightweight Acetal Plain Bearing option is low maintenance and can handle working loads up to 300Kg, while the Stainless Steel Dynamic option offers the lowest friction for maximum performance and is perfect for fast running systems. Both options can be used with rope and wire.