Instruction:

Easy-to-use, self-contained boresighting system fits in the chamber of your rifle or pistol and projects a powerful red laser beam aligned with the bore axis for sighting to the point-of-aim without firing a shot. Works with scopes, holographic red dot sights, and variety sights. Durable, machined brass housing looks like a cartridge case but actually contains the entire laser system and batteries. Insert the batteries and screw the cap on the housing to turn on the laser; remove the batteries to turn off. Insert the entire assembly into the chamber, gently close the action, and aim at a target 20-30 yards away. Adjust windage and elevation of the scope or sights so point-of-aim is zeroed on.

Power: <5mw
New Cartridge Laser Boresighter is designed for 12 Gauge shotgun chambers
Chamber-Mounted Laser Helps You Sight In Rifle Or Pistol Without Firing A Shot
Features:
Laser wavelength, 632-650 nm.
Sighting range, 10-75yards.
Dot Size: 1.5" @ 100 yds
Package included:
Battery: 3x AG5 (included)