Review on Length Threads with Stainless Steel Internal Construction by Bobby Martinez

Used to hold the rear detent on my modern sporting rifles. Deer hands fall. (AR-15 style semi-automatic rifle). Now I can remove and replace the buffer tube extension without worrying about the retainer and spring hitting my face. Great little "upgrade" if you want to call it that. You have to drill and tap! Vermont American 21660 Size 4 x 40 NC Tap #43 Combination Drill <-- Perfect! B000CFLA02