Times distances up to 1/2 mile. 1/100 sec. accuracy. 126 time recallable memory. Extra sensors (additional) enable system to start on movement and record split times (up to 9). Time is stopped when infrared finish line beam is tripped. Includes hand-held timer, one set of infrared electric eyes with built in transmitter, touch start pad, two tripods, microphone starting sensor, carrying case and instructions.