Competition Electronics ProChrono LTD Digital chronograph Large 4-digit LCD screen Up to 9 strings of up to 99 shots each memory capacity Review individual shot velocity, average, high, and low velocity, standard deviation and extreme spread 20-9,999 FPS measurement range +/-.5% of measured velocity, or better Minimum of 500 ms time between shots 31 ns crystal-controlled shot timing resolution (8000 counts @ 4,000 FPS) 1/4" x 20 tripod mounting hole thread 3/16" x 16" guide wire Uses one 9-volt alkaline battery (not included) Approx. 20 hours of battery life Onboard storage for spare battery 15mA power consumption 20-100 deg. F operating temperature range 16" long x 4" wide x 3-1/4" high Weight: 2.1 lbs. 2-year warranty against defects Made in USA Please Note: This device is meant to be used outdoors with good lighting conditions to register properly. For use indoors it is recommended to use the Competition Electronics Indoor Lighting System, sold separately.