The Ballistic Precision Chronograph provides accurate velocity measurements across a wide range of shooting conditions. This Chrono has the ability to provide much better accuracy than other chronographs on the market (+/-.25%). Although technologically advanced, the unit is designed to be simple to operate, displaying velocity in Feet per second or Meters per second on the large built in LCD screen. The Chrono can also deliver the shot string velocity data through the 15' foot audio jack cable (included) to an iPhone or iPad. A free App is available for download that displays the velocity of each shot on the phone screen and records it with other data identifying the load and environmental conditions. The data is stored and can be exported via Email or simply recalled for reference at a later date. Measures from 5 to 9,999 FPS. There is a 1/4-20 threaded insert on bottom of housing for tripod mounting, operates on a 9 Volt battery (not included). Each unit factory calibrated to within +/- 0.25% accuracy Ideal for Firearms, Archery, Airgun and Paintball Simple operation, large LCD screen Meters Per Second (MPS) or Feet Per Second (FPS) readings Extra wide sun screens for added shading in full sun operation Option to interface with Smartphone via included 15' audio jack cable App displays velocity, logs data, notes, weather condition.