Shooting Chrony 7000068 Archery Chronograph, Green Measures the speed of bullets, arrows, etc. from 30 feet per second to 7000 feet per second. Can go with you anywhere, meaning it is really easy to transport. Made of 20 gauge steel but weighs less than 2 1/2 pounds Powered by a single 9 volt battery. Measures speed within .5-Percent accuracy.