Here's the classic way to demonstrate the resolution of forces, uniform and accelerated motion and kinetic and potential energy. Our deluxe-apparatus is durable, accurate and easy to use. Of sturdy all-aluminum construction, it folds for storage and clamps to an angle from 0 to 45°. Rugged PVC protractor has a high-resolution scale that won't wear off despite hard use. We feature a special low-friction plastic pulley to accommodate any size load. Instructions include projects and problems. Weight: 4 lb. 6 oz.