Small pocket chronograph X310 from XCORTECH. Its dimensions are comparable to a GoPro camera. It is easy to operate and allows you to set different weights and calibers of ammunition. It provides two power options: 1x AA battery (not included in the package) or connection via Micro USB to any USB port. High-quality DOT Matrix backlit LCD display High-density IR detector for fired projectiles 3 memory options for storing ammunition weight and caliber Memory recording of speed and ROF for 25 frames Tripod mountable Muzzle velocity range: 1 mps – 300+ mps (3 fps – 980 + fps) R.O.F. range: 75-6000 rpm Muzzle energy range: 0.01-800 Joules Dimensions: 72 mm x 47 mm x 51 mm