Brand New clip on sensor for beat amplifiers and timing machines. This highly sensitive pickup is easy to use, rugged, and compatible with ALL TIMETRAX timing machines as well as most Beat Amplifiers/ Telephone Listeners that accept an acoustic pickup. 1 year NO-HASSLE Guarantee! I have been PERSONALLY making these since the early 1980's and this barrel design with clip is my own invention which has been and continues to be knocked off by competitors. Included in this auction is ONE (1 piece) of clip on sensor pickup. All other equipment shown in the photos are simply to illustrate the possible uses/applications. QTY Discounts Available! S/H/I via USPS for the USA with Delivery Confirmation @ a fixed cost of $ 3.95, International via USPS AIR Priority Mail $ 25.