Tested and recommended by the National Tactical Officers Association in the USA, the Sightmark®9mm Boresight significantly reduces wasted cartridges and shells. Chamber the device in your 9mm Pistol or Rifle like a regular cartridge, and a red laser dot shows exactly where you're aiming. Simply adjust your sights or scope, and save your extra ammo for the hunt. Includes a carrying case, three (2) AG3 batteries, and instructions.