A must have for your ar-9 build - Guntec USA AR 9mm Cal CAR Buffer and Spring Set

This buffer and spring is the BEST bang for your buck. It slows down the bolt cycling for reliable feeding of 9mm ammunition, compared to your standard ar15 buffer and spring . For the money, this is the best affordable option out there. In my book this is a MUST HAVE. Absolutely no issues for me once this buffer was installed. You won't regret purchasing this buffer and spring for your ar-9 build.