Magpul M-LOK T-Nut Replacement Set Replacement hardware pack designed for Use with all M-LOK accessories Made of 4140 chromoly steel with a Mil-Spec manganese phosphate finish Supplied with two T-Nuts as well as two different length button-head cap screws to ensure compatibility with various hand guard or forend thicknesses A self-locking reusable thread patch is added to the screws to ensure a secure fit upon installation Made in USA