Low-Friction Triple-Tandem Plastic Pulley, 25/38/50mm Diameter Physics_Alternative Energy and raised-graduated for shatterproof bench

and raised-graduated for shatterproof bench use

Twelve-ball drilled set in a foam-lined plastic case with two each of aluminum

this metal wave apparatus pairs the rotary handle with a degree scale so students can read phase against vertical displacement

Ratchet-stopped nickel-plated brass 25 mm micrometer screw gauge reading to 0

Low-Friction Triple-Tandem Plastic Pulley, 25/38/50mm Diameter Physics_Alternative Energy and raised-graduated for shatterproof benchTriple tandem plastic pulley with 25 38 50mm ball bearing wheels on an open sided 17. 6cm steel frame, eliminating cord threading during setup in compound pulley experiments.