Rugged Plastic Pulley With Deep V-Grooves Mounted On A Metal Clamp. The Sheave Is 50Mm In Diameter. Clamp Can Be Mounted On Surfaces Up To 35Mm Thick. Rugged plastic pulley with deep V-grooves mounted on a metal clamp. The sheave is 50mm in diameter. Clamp can be mounted on surfaces up to 35mm thick.