4-Step Differential Metal Pulley, 20/30/40/60mm

The Eisco 4-Step Metal Pulley Differential is a sturdy classroom apparatus for demonstrating mechanical advantage and the principles of pulley systems. The four pulley diameters — 20mm, 30mm, 40mm, and 60mm — allow students to compare force ratios and explore how varying radii change the work required to lift a load. Each pulley has a 4.75mm inner gap. The painted black and blue metal unit is mounted on a 4-inch-long, 3/8-inch-diameter rod for easy attachment to standard lab stands. Overall dimensions are 6.75" x 3.5" x 3", making it well sized for tabletop physics demonstrations.