Introduced in 1978. Patridge front sight and an adjustable rear sight. Slide marked with the "COLT SERVICE/MODEL ACE in a diamond .22 LONG/RIFLE" followed by the Rampant Colt on the left side, "ACE" in a diamond on the right side and the one line address and serial number on the right side of the frame. The barrel chamber is marked "COLT/CAL. . 22 L.R." and the left side of the frame under the grip is marked "COLT ENG". The pistol is moderately engraved with wedges of floral scroll and punch dot engraving. The flat surfaces are polished nickel with a brushed matte nickel on the balance. Serrated hammer and trigger, arched mainspring housing, nickel Colt marked magazine and fitted with smooth pearl grips with gold Colt medallions. Complete in a brown leather wrapped Colt case with rust orange fitted lining.

Near new with only slight handling/storage marks. The grips are excellent. The right panel has a flaw in it. The case is excellent.