suitable for KS3+. Made from rigid ABS plastic, these trolleys have accurately aligned, very low friction wheels allowing for high quality data. The two position firing pins have a locking catch for safety and the trolleys have velcro pads for inelastic collision experiments. The trolleys are stackable and can withstand loads up to 60kg. 600g Mass. Dimensions: 310mm (L) x 130mm (W) x 90mm (H).