Our UL-NW-1-B is a good choice for most longrifles using barrel pins. Milled brass, the dovetail is 0.500" long, by 0.47" wide. The base is .050" thick, ideal for thin wall barrels. The blade is 0.075" thick and stands 0.19" above the base. Most rifles will use three underlugs, while barrels longer than 42" use four. Made in the U.S.A. This underlug is good choice to replace the now discontinued UL-SPW-3 underlug.