The Caldwell® G2 literally flips conventional chronograph technology upside down. By inverting the system the G2 is capable of measuring in adverse light conditions making the measurements more accurate than conventional chronographs, even indoors. The light sensors were spaced 18" apart for more accuracy and the sunscreens have self-contained LED lights when a little extra light is needed. Collapsible and compact, the system is quick and easily deployed from its heavy duty storage case. Higher accuracy was achieved by using a high speed 48 MHz processor and by designing a circuit with an advanced data interface that allows each unit to be computer calibrated at the factory after assembly. The end result is the ability to provide much better accuracy than other chronographs on the market (+/- .25%) and measures from 5 to 9,999 FPS. 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 App also automatically calculates Average Velocity, Standard Deviation, Min, Max and Velocity Spread for the shot string. The data is stored and can be exported via Email or simply recalled for reference at a later date.