This daylight-visible 532-nanometer green laser creates a dot that can be seen up to 100 yards with the naked eye, meaning you can sight-in anywhere from 10 yards to 100 yards away. The new Kryptonyte LBS System fits any handgun*, rifle or carbine from .22 to .50 caliber and .51 to .75 caliber as well as 12 to 20 gauge shotguns. The Auto Pwer Control digital circuitry ensures a bright and steady dot for the full 1-1/2-hr. life of the CR2 lithium battery. *Four-inch minimum barrel required