The Forward Controls CNF is based on the TDP spec castle nut, with couple of changes: Staking notches angle changed from 45 to 30 degrees, this results in longer (25% longer than TDP spec) and deeper notches than found on TDP castle nuts. Number of staking notches increased from 3 to 4, spaced equally on the CNF. This means that 3 staking notches will be visible, giving the user more staking locations. Coarse serrations on the wrench side of the nut, a single use feature to make it easier while rotating the CNF towards the end plate.