As much as I like Fortis products, I'm not sure if aluminum castle nuts are the way to go on a hard use gun, duty grade, life saving gun. Granted, like the video said, they haven't had one fail to their knowledge. I have several and they've haven't failed either. BUT.... Something about a steel castle nut with proper staking. Maybe that's my inner Will Larson talking... plus a regular castle nut is $3.