T-nut

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.

In 1969, the first four-prong T-nut with an eight-sided base was patented.

Unlike standard round base T-nuts, eight-sided T-nuts can be fed efficiently and reliably via machine.

The eight-sided T-nut base has become the standard configuration for T-nuts inserted by machine.