A Sightmark® Laser Pistol Boresighter gets you back on target faster and without wasting precious ammo. It's convenient, accurate and easy. All you do is chamber the unit as though it were a round, and a red laser dot will show you exactly where your aim will land the shot. From there, you can adjust your scope or sights without ever firing a shot! Several caliber-size housings are available to fit all of your favorite firearms. Don't replace... re-calibrate with a Sightmark® Laser Pistol Boresighter!