Petzl Tandem Pulley Spring 2009 The Tandem Pulley by Petzl is a double pulley with aluminum sheaves designed for Tyrolean traverses on rope. The Tandem Series of pulleys are designed for movement on a Tyrolean traverses. The in-line sheaves and fixed side plates make them very stable. The three versions allow for numerous configurations, depending on the bearing and the efficiency required. They are simple to use and can also be integrated into complex hauling systems. Specifications: Weight: 195 g Breaking strength: 24 kN Working load: 10 kN For use with ropes of maximum diameter 13 mm Certification:CE / UIAA Features: Sheaves mounted on self-lubricating bushings for good efficiency. Maximum allowable speed: 10 m/s. Accepts up to three carabiners to facilitate use.