Forward Controls Design

The TDP spec castle nut is a simple and robust fastener that is almost perfect for the job it's tasked to perform. CNF (Castle Nut, Forward Controls) is based on the TDP spec castle nut, with now 4 staking notches that are longer and deeper (30 degrees notch vs. TDP castle nut's 45 degrees) and coarse serrations on the wrench side of the nut. The CNF has longer and deeper notch that once installed and staked, will not loosen without the user's deliberate action. CNF is billet machined in 4140 PH steel, and black nitrided. As with everything Forward Controls Design produces, it is proudly made in the USA. 4140 billet steel AR15M16 castle nut Mfg: Forward Controls Design Llc.