This is an early barrel for a World War One vintage Colt 1911 Automatic Pistol in .45 ACP. It has the P and H government inspector stamps on top of the running left to right respectively. According to Clawson's book, this barrel would be correct for a US Army Model 1911 from serial number 24,251 up to 120,000...circa 1913-1915. The "P" is the Colt proofmark and the "H" is the provisional inspection mark of gov't inspector "Francis L. Hosmer". Early production 1911's really saw some hard use...from the moment they were issued, the 1916 Expedition to Mexico, the First World War 1917-18, missions in South and Central America during the 20's and 30's...WW2 1941-45, Korea 1950-53, and probably a few of these old war horses even saw action in Vietnam during the 60's. That said, far more early 1911's survived their original barrels making these early ones, in any condition, an absolute BEAR to find these days. This one is in Fair+ to Good condition and has seen plenty of action but it's never been refinished or buffed. There is about 30% original finish remaining overall and the "P" and "H" stamps are still clear and completely legible. No modifications or monkey business. The bore has all of its rifling intact but very frosty with light pitting down in the grooves...no rings or bulges...grades to Fair+ Overall. A good example of an original US Army Colt barrel to make your early 1911 correct.