Deluxe Loop de Loop (LSE) This high quality Loop de Loop apparatus easily demonstrates the transformation of potential energy to kinetic energy. Use the built in ruler to measure the distance the ball has dropped from its starting point at the top. Measurements are in centimeters. Device comes with two balls and a sturdy wooden base. Also, the Loop de Loop features a two-sided back drop plastic disk that allows for measurements in degrees or cm when the ball traverses the loop. Qty :