The Rope Wrench Pulley is designed for use with the Singing Tree Rope Wrench. It has parallel side plates, to accommodate the Rope Wrench Tether. ISC lightweight Eiger Pulleys are made from high strength Aluminium and fitted with tamper-proof rivets. ISC Eiger Pulleys are fitted with Bushings, which are ideal in lightweight applications. The RP281 has been designed with parallel side plates specifically for use with the RP280 Singing Tree Rope Wrench and the Sterling Rope tether, RT270. Made outside the U.S.A.