The Gemini Double Pulley by Petzl. The GEMINI double pulley is equipped with an auxiliary attachment point for use in Technical hauling systems. Final SALE: For safety reasons, we cannot accept returns on load-bearing Climbing equipment. Sorry for being so mean. Features of the Petzl Gemini Double Pulley Special side plates designed for use with a Prusik friction hitch in progress capture systems Parallel mounted sheaves and auxiliary attachment point for creating different types of hauling systems Sheave mounted on sealed ball bearings for excellent efficiency Compact and lightweight