Brownells Brn-4 Buffer Retainer
Brownells Brn-4 Buffer Retainer, The BRN-4 Buffer Retainer is the perfect buffer retainer for HK416 or MR556 type firearms. Machined from stainless steel to exacting dimensions. Will not work in AR-15/M16 firearms. BRN-4 or HK416/MR556 lower receiver with roll pin retention of the buffer retainer is required. Mfg: Brownells