HK 91. Suppressor ready for 51-t aac Advance armament AAC 7.62 SD or AAC 7.62 SDN-6 or AAC ranger 7. i have 22 box magazine, that hold 20rds with Hk/G3 markings and 1- box magazine hold 25rd. Nikon scope 4x12x40 with quick detach mount. it's dated with the serial number which is the late 60s early 70s