Fortis Castle Nut, Black, Anodized Finish, Mil Spec

The Fortis Standard Castle Nut is manufactured from a solid piece of billet aircraft grade aluminum that offers a significant weight reduction to your castle nut. If you're trying to save ounces, this is a great way, but without sacrificing durability. The castle nut will fit onto mil-spec buffer tubes and quickly upgrade the form and function of your build.