T NUT - Steel M4 to M12 | White & Yellow Plating Flush Surface Design Flanged Body with Serrated Prongs for Enhanced Retention

A T-nut which can however also refer to a rivet nut or an insert nut and likewise drive-in nut is a type of nut used to fasten a wood particle or composite materials workpiece leaving a flush surface.

It has a long thin body and a flange at one end resembling a T in profile. The flanges of T-nuts often have hooks or serrations on the prongs that dig into a wooden work piece as the bolt is tightened from the opposite side of the piece providing better retention.

T-slot nuts which are used in work-holding in machine tools. T-slot nuts fit in T-section slots in the machine work-table and are used in conjunction with studs and clamps to provide flexible means of holding workpieces in place.
Weld nuts which are similar in appearance to t-nuts. They lack the prongs which penetrate into wood. Weld nuts are usually spot-welded into place on metal.