CVLIFE Green Laser Bore Sight Collimator Boresighter for .22 to .50 Caliber Rifle, Sights and Riflescope Power of the laser: 2mW; Class of the laser : ClassIIIA; Easy and convenient to mount. Four bore adjustable adapters are easy to mount to any .22 to .50 caliber handguns and riflescopes. Simply choose the proper caliber adapter and slightly place the laser bore sighter in the muzzle. NOTE: Battery must be inserted negative end first. The boresighter will emit a straight green laser beam, providing precise reference for zeroing in your sights or scopes. The green laser is visible whatever it is in broad daylight. Made of high quality aluminum with free premium case. And this bore sight kit comes with a screwdriver, two screws, a Allen wrench, four adapters, and a Lithium battery.