Part number 13-1347-AS includes (qty 1) engagement screw and (qty 1) 13-1346 lock nut. In older model Top Guns these items were silver (bright anodized). They now have a hard coat anodizing, resulting in a dark grey finish, they are otherwise (dimensionally) the same. Sold individually.
If the longer screw is needed, see part number 13-1685-AS