Sturdy metal construction throughout Ideal for demonstration of wide variety of mechanics principles 2" (5cm) diameter sheave Completely rotatable pulley for flexibility in experiment setups Adjustable to 9" height with 1.9" maximum clamp opening Sturdy, metal clamp pulley can be used to demonstrate a wide variety of mechanics principles. The metal sheave is 5 cm in diameter and can be adjusted from flush with the tabletop to 13 cm above it. Pulley can be rotated to 360º to suit any experimental setup.