StrongTools Green Laser BoreSighter for .177 to 12GA Caliber Rifle Scope Handgun Hunting Green Dot Boresight Kit with Press Switch Bore Sight with 2 Pieces 800mAh Battery-Green-

Instructions:1. Assemble the battery into the laser boresighter. 2. Select the proper adapter that fits in the barrel of your firearm.3. Assemble the adapter on the small end of the laser boresighter, then screw the adapter tight to make sure the adapter will be hold well.4. Push the small end of the boresighter with the adapter into the barrel of your firearm. Make sure the boresighter is inserted in untill it is sung with the crown of your firearm.5. When you turn the laser on, a small red/green laser dot will be emitted. And then you can adjust your scope’s windage and elevation so that your crosshair aims at the red/green dot.Warning:Keep boresight laser beam away from eyes.Before boresighting your scope, make sure that the firearm is unloaded and the muzzle is pointed in a safe direction.After the firearms is boresighted, make sure to remove the boresighter and adapter from the firearm.Specifications:Material: Aluminum.Weight: 1.65ozLength: 6.57"Big end Diameter: 0.8".Small end Diameter: 0.169".Shortest barrel available: 1.95".Laser wavelength:  Red:630-680nm; Green:532n.Max. Output Power: ? 4.9mW.Laser class: IIIa.Laser Color: Red or Green.Batteries type: CR2 3V 800mAh, non rechargeable.Packing List:1 x Laser boresighter 12 x Adapters (will fit almost all calibers from .17 to 12ga)2 x CR2 battery (800mAh each battery) 1 x Screwdriver 1 x Instructions 1 x Padded storage box