Our UL-NW-S2 is a bit longer, for use where a larger stronger joint is required. We recommend using this lug to support a sling swivel mounted on your musket's forend. Milled steel, the concave base is .500" wide, .740" long. Use 96% tin + 4% silver lead free solder. It melts at low temperature, but is stronger than lead-tin solder.