Carlson's Universal Hammer Spur Extension Silver 

The Universal Hammer Spur Extension by Carlson's is an easy way to increase the ease of use for nearly every firearm with a hammer. The extension is ambidextrous and features knurled ends for a positive grip. Installation is quite simple: slide the extension over the hammer and tighten the set screw with the provided hex wrench. The opening of the extension is approximately 1/2" wide by .2" in depth.