Performs high quality motion experiments through its low friction design. Because the PAScar's body and plunger are made of polycarbonate plastic, these carts have a mass of just 250 grams. Each cart includes both a spring plunger, magnets and velcro tabs for collision studies. The PAScars come in a set of two, one each of red and blue, and are compatible with all PASCO Dynamics Tracks and accessories.