FEATURES of the Petzl Tandem Pulley Aluminum sheaves mounted on self-lubricating bushings for efficiency Accepts up to three carabiners to facilitate use SPECIFICATIONS of the Petzl Tandem Pulley Weight: 195 g Case Quantity: 10 Rope Diameter: Maximum: 13 mm Sheave Diameter: 21 mm Efficiency: 71% Working Load: 10 kN Breaking Strength: 24 kN Certification (s) : CE EN 12278 - UIAA ALL CLIMBING SALES ARE FINAL.