Timetrax Model 185 Clock Timing Machine w/ built in Beat Amplifier.   The unit comes with Instruction Manual and Book of Clock Train Tables.   Also included is a clip on highly sensitive sensor pickup.   The unit is battery powered by 4X AA Alkaline Batteries (not included).  2 year no-hassle warranty.  We are designer & manufacturer of this product.   This product can be used to digitally adjust the balance of a mechanical movement & the rate as well.    The built in Beat Amp is a useful feature to facilitate beat adjustments as well.   FREE Domestic Shipping via USPS.   

2 timing ranges: 60 – 1999.9 & 2000 – 19,999 Beats Per Hour

Timetrax Model 20 Rugged clip on sensor included

Balance Mode & Averaging from 2 – 130 cycles

Thanks for looking, Adams Brown Company, Cranbury NJ 08512