• Component: AR-15 castle nut
  • Material: Carbon steel
  • Finish: Phosphate
  • Thread: Mil-spec 1-3/16"–16 (NOT commercial)
  • Use: Locks receiver extension, captures end plate, takes standard armorer's wrench

Full details and secure checkout: https://3crtactical.com/standard-steel-castle-nut-1300/?utm_source=armslist&utm_medium=referral&utm_campaign=listing