This apparatus consists of a curved track with a base at one end. On the base is a support to hold a ball at the proper height for a center-to-center collision with a second ball rolling down the track.
- 1x 25 cm one-piece track
- 3x balls (12 mm diameter): 2 steel, 1 glass
- 1x Plumb bob
See the Buying Guide for this item's required, recommended, and additional accessories.