The Buck Side Swivel is a heavy duty aluminum single sheave pulley that has a 5/8" diameter rope capacity with a 2500 lb working load limit. The "Side Swivel" plate allows rope to be installed/removed without disconnecting it from the anchor point. Specially designed side plates are ideal for use with progress capture Prussics. Swivel eye prevents twisting of ropes. Ideal for building mechanical advantage with the Ox Block.