The F1 Chronograph measures the speed of bullets and other projectiles from 30 to 7000 fps. It can be mounted on a tripod or placed on a table and runs on one 9 volt battery (not included) for up to 48 hours of continuous use. The F1 Chronograph features a large display that shows numbered shot velocities. Includes a jack for use with an optional Chrony Ballistic Printer (sold separately). Covered under a 3 year limited factory warranty.