Colt AR-15 "SP-1", .223 cal. semi-auto rifle. Serial #SP27962 mfg. 1973. Excellent condition. Nice early version of the Vietnam era M16 with triangular forearm, bayonet lug, no forward assist, hollow pistol grip, fixed buttstock, 20" skinny barrel. Excellent chrome bore, birdcage flash-hider and fixed carry handle. Finish is nice at 98%.  Triangular forearm. Correct 20-rnd Colt magazine and manual. These are becoming quite collectible and this one is super nice. A must have for your collection! Very desirable!