Sigma T-Nuts
In 1964 Sigma introduced and patented the first 4 prong t-nut with the now familiar 8-sided base. Unlike the standard round base t-nuts, the new Sigma T-nuts could be fed efficiently and reliably by machine. The 8-sided t-nut base has become the standard configuration for t-nuts inserted by machine. Sigma Tool & Machine is one of the world's largest manufacturers of T-nuts for the upholstered furniture industry.
Today Sigma continues to manufacture quality t-nuts designed for machine insertion Machine drive t-nuts are available in the popular ultragrip style as well as step barrel t-nuts in a variety of sizes, options and finishes
