PRO PACE CLOCK / SHOT CLOCK- By Colorado Time Systems. Four large 10" LED digits with improved clock accuracy allows synchronization among multiple pace clocks. Pro Pace Clock adds additional training features to the Basic Pace Clock/Shot Clock. The additional timing modes include: lap counter, pace clock with cumulative splits or lap splits, relay exchanges, break out times, turn speed, start reaction times, and single lane timer. The clocks operate with or without a timer or controller. Displays minutes and seconds up to basic 59:59 and rolls over to 00:00. Pro Pace Clock can be run as a stand alone unit, or set to run in a series of pace clocks. Includes: Internal battery and horn. 110 volt/60 Hz, rechargeable internal battery. Will run more than 6 hours before recharging. Optional Ultimate Pace Clock Controller ordered separately.