Eliminate the need to run control cable to each clock. 7.9" H LED numerals are visible within 300 feet. Extremely reliable and easy to use shot clocks come with a battery powered wireless controller and two wireless shot clocks which are powered by built-in, rechargable batteries or 110v AC power.  4 user-programmable wireless frequency settings.  Module INCLUDED for controlling via the SK2229R or SK999 Portable Scoreboards.  Counts up or down from 1 to 99 seconds. Gametimer numbers are 4.7".  Loud, built in horns included. 2 100' data control cables included.  Recommended for portable use only. Each clock measures 10.2"L x 15.6"W x 23.6"H. Weight: 12 lbs per clock. Stand sold separately.  For indoor use only.