The key piece of equipment in motion experiments is the timer and this is a real workhorse. The vibrator leaves sharp, easy-to-interpret points on the tape, and can even leave up to four tracks on the same 3/4″ wide tape by adjusting its position. Uses inexpensive waxed paper tape (it will accept any tape up to 5/8″ wide) and operates on 3 to 6 VDC from either batteries or a power supply. You will also need a C-clamp. Supplied with one roll of tape and instructions.