Allstar 1/2-20 Fine Thread Slider Box T-Nut features a slider box t-nut that has a 1/2-20 fine thread. The t-nuts have a 0.750 inches slot built-in for easy adjustment. There is no second wrench that is needed to tighten or loosen. It is designed to be used with Allstar slider box part 60186 or 60188. It is backed by a 90-day limited factory warranty and sold individually.