Petzl Tandem Trolley One Size. Specifications for Petzl Tandem Trolley: Manufacturer: Petzl Weight: 6.8 oz Breaking Strength: 24 kN Rope Capacity: Maximum diameter 13 mm Working Load Weight: 10 kN Pulley Type: Transport Features of Petzl Tandem Trolley Sheaves mounted on self-lubricating bushings for good efficiency Attachment point accepts up to three carabiners to facilitate use Package Contents: Petzl Tandem Trolley Petzl P21: Tandem Trolley One Size