Forward Controls Design CNC Billet Machined Castle Nut for A5 Length RE Black CN5F 17-4 SS. Staking notches angle changed from 45 to 30 degrees this results in longer (25percent longer than TDP spec) and deeper notches than found on TDP castle nuts. 2. Number of staking notches increased from 3 to 4 spaced equally on the CNF. The castle nut is to be staked in two places we're not advocating staking in more than two places CNF's 4 staking notches mean that at all times 3 will be visible and available for staking it simply gives the user more staking location options. 3. 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. Specifications for Forward Controls Design CNC Billet Machined Castle Nut for A5 Length RE: Manufacturer: Forward Controls Design Color: Black Fabric/Material: 17-4PH Stainless Steel Finish: Nitride Features of Forward Controls Design CNC Billet Machined Castle Nut for A5 Length RE Four total 25percent longer staking notches Coarse serrations for easy installation Package Contents: Forward Controls Design CNC Billet Machined Castle Nut for A5 Length RE Forward Controls Design CN5F 17-4 SS: CNC Billet Machined Castle Nut for A5 Length RE Black