It has 8 interchangeable expanding arbors will bore sight most .177 - .50 caliber firearms rifles, handguns, and scopes.
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.
When you turn the laser on, a small green laser dot will be emitted. And then you can adjust your scopes windage and elevation so that your crosshair aims at the green dot.
Keep boresight laser beam away from eyes.
After the firearms is boresighted, make sure to remove the boresighter and adapter from the firearm