<b>Specifications:</b><br> Material: High Quality Aluminum<br> Max. Output Power: less than 5mW<br> Class: IIIa<br> Color: Green<br> Wavelength: 630-680nm<br> Boresighter's Weight: 1.34oz<br> Boresighter's Length: 6.1" / 155 mm<br> Length of rod that fits into the barrel: 2.4"- 3.5" / 60 mm - 90 mm (tapered) <br> Head Diameter: 16 mm<br> Tail Diameter: 5 mm<br> Dimensions: 170mm x 20mm<br> Range: 330ft/100m<br> Power:1x CR2 battery<br><br> <b>HOW TO USE IT?</b><br> A. Assemble the battery into the boresighter. <br> B. Select the proper adapter that fits in the barrel of your firearm. <br> C. Assemble the adapter on the small end of the laser boresighter, then screw the adapter tight to maker sure the adapter will be stable on your barrel. <br> D. 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. <br> E. When you press the switch button, a bunch of green beam will be emitted. And then you can adjust your scope’s windage and elevation so that your crosshair aims at the green dot. <br><br> <b>Package Includes:</b><br> 1x Green Bore Sight (Boresighter) <br> 9x Bore Adapters<br> 4 x Spare screws<br> 1 x Screwdriver<br> 2x CR2 Battery<br><br> <b>Warm Tips:</b><br> --Keep boresighter's beam away from eyes. <br> --Before bore sighting your scope, make sure that the firearm is unloaded and the muzzle is pointed in a safe direction. <br> --After the firearms is bore sighted, make sure to remove the boresighter and adapter from the firearm.