[ithacaartist]

Hiya Mike, and welcome...

Let's call this a byf 42! The cursive, lower case L is part of the complete serial number--4449 L. Your mag appears likely to be from before 1942, though, 'cause by '42, they had aluminum bottoms, and the last versions marked "fxo"--the code for Haenel-Schmeiser--were actually constructed differently, forged then machined. I'll bet when we see the body of your mag, it will be nickeled sheet steel with crimped and staked construction.Your mag was issued for serial #2901 L, and the "+" designates the first spare mag--the primary would not have a plus sign. A third mag, if it existed for that gun, would have "++" on it. These are military marks.

I'll take a callow stab at value for you: I'd say it's collectible, unless subsequent pics bring up issues that knock it out of that category...if all the numbers legitimately match and the condition is demonstrated to be not too bad. I'd expect to be payin' $1.5k minimum for it, but, like I said, the details are in the hi-res pics, when they get posted, and condition is everything.