The MultiChron is a hand-held stopwatch from AiM that is capable of timing 4 cars at once! Start or stop all 4 timers at once, or each individually. Huge memory holds 99 laps per car, with up to 9 split times per car per lap. Display fastest lap times at any time, even while the watch is still running. A secondary backup battery keeps the memory intact if the primary battery dies. Backlit display window measures 1" x 1 1/8" (25.5 x 29 mm). Weighs less than 4 ounces (just 100 g) including batteries. Includes quick-release lanyard.