that particular mag is the first attempt at the effort to get away from the sheet steel folded mag tubes. It is formed with a process know as "Cold drawn formed tubing" but everyone calls the process extruded... That particular mag is quite thick in places, and subsequent mags, made thru the years, in this fashion show varing degrees of lightened areas and thinner wall thickness in certain spots. The mag shown is probably the heaviest production Luger mag ever made... the flat button is unique to the very early 1900 commercial, and this variation of late 20's to early 30's mag. But, the flat button design is quite different between the two. This flat type button is also located with a square pin / rivit end to fasten it into the follower, so it cannot rotate if it should work loose... this is because the button is relieved on one side to clear the thick ridge it runs along vertically on the tube... The next variation of this mag was slimmed down a bit, and I think it the most pleasing of all Luger mags to the eye... soon after the "code 122" & "fxo" styles appeared, finishing up with the East German post war mags... I think it (this early type) was a bit complex for military acceptance. most, if not all had police or maybe even commercial connections.. (high serials?) They are pretty neat, and a bit rare... probably will go for a pretty good price, looks right as rain to me! ... Best to all....Til...lat'r....GT
