obsessed w dbls - yes, it does have a retractable sling. i pulled it out about ten inches with no trouble but didn't go any further, not knowing what it was all about. Top side of both barrels are marked KRUPP STAHL in a circle and GERMANY across middle of circle. Underside each barrel stamped KRUPP. Each barrel also stamped with two hexagonal impressions with a raised "S" inside and a smaller stamp that i can't read. I did not inspect inner barrels and don't have the gun here to do so. I can say there was no evidence of rust or pitting anywhere else on the gun. I'll ask my bro-in-law to inspect. Also I'll try to add photos of details described above asap. thanks.