This simple polymer add-on rail clamps onto the magazine tube of your Remington, Mossberg, Winchester, Benelli, or other 12 gauge shotgun that has a magazine tube measuring approximately 1 inch in diameter. Putting this mount ahead of the pump on pump action guns or in front of the forearm on semi-autos allows you to mount a Streamlight TLR-1 or TLR-2 series light at the 6 o'clock position. There, it can be easily reached by the support hand while the shotgun is being fired from either shoulder.