These plastic pulleys have deep V-groves and are mounted on a metal frame with hooks on two ends.
Pulleys are often used as parts of compound machines. They function as helper machines, easing the lifting power. In fact, a pulley system can cut the force necessary to lift a very heavy object in two, four, etc., depending on the designed system. With these pulleys you can study and measure the force and distance trade off with compound machines. These pulleys are good for science experiments as well as functional tasks.