Exotic Nutrition's Sandy Trimmer Track is a track that fits into the Silent Runner for nail trimming use. Sharp nails can cause scratches. One way to avoid this is to trim your pets nails on a regular basis. The new Sandy Trimmer Wheel makes this task easy! This is a glider-safe plastic track, with soft abrasive material permanently bonded to it. The track is washable for easy maintenance. This track has a soft sand abrasive interior finish. Your pet's nails are trimmed automatically as they run in a Silent Runner Wheel. Simply disassemble your Silent Runner, replace the regular track with the Sandy Trimmer Insert, and place the wheel in your pets cage for 24-36 hours to trim their nails during use. Directions: (See Video Below) Remove the standard running track on your Silent Runner wheel. Begin by inserting the corner of the Sandy Track into the molded edges of the back panel (black) for the Silent Runner wheel. Once the corner edge is pushed in, begin working the sandy track all the way around the wheel into the groove. Once completely in the groove, push the clear connector into place connecting both ends of the track. Set the front wheel panel on the sandy track, and starting with the side away from the connector, work one small section of the sandy track into the front wheel panel groove (panel with the openings). Once a small section of the track is in the groove, apply pressure (squeeze down) all the way around the wheel until the track is in place. You may need to push the last section near the clear connector in with your fingers. Set the wheel down on a hard, flat surface and apply pressure all the way around the wheel to secure the track in place.