Simply chamber the boresight like a regular bullet and a laser dot will show exactly where the rifle is aiming. It's easy to sight in any scope without firing a single shot. Multiple caliber & pistol. Precision accuracy. Perfect for hunters, competitive shooters and law enforcement. Most accurate gun zeroing system. Reduce wasted cartridges and shells. A lightweight carrying pouch protects the laser for convenient use in the field. Protected by a Limited Lifetime Warranty.