The Sightmark Universal Laser Boresight provides the most convenient and accurate method for sighting in rifles and pistols of all types. Simply place the base of the boresight onto the end of the barrel of your weapon and it will attach magnetically. A laser dot will show exactly where your gun is aiming; it's easy to sight in any scope without firing a single shot. Live fire is only needed to fine tune the weapon being sighted in order to compensate for inconsistencies, such as bullet drop due to distance. Perfect for hunters, competitive shooters and law enforcement, the Sightmark Universal boresight is sure to take the frustration out of sighting in almost any gun.