Winder side has Thompson logo plus "wind to 9 or 11 clicks". Plate below loading port indicates "Thompson SMG Type L 50rd for 1928 model 9 or 11 clicks" & further stamped below that with "U". Side opposite winder has on plate below loading port Auto Ord. Corp. address & patent info & also a "U" below. A scarce original drum in good plus condition with some spots of oxidation, a slight dent on the base (opposite winder) & a general patina finish. (02-5099/NW). $350-500.