Some observation on a couple of No5 Mills. I document this stuff for my own records but might as well share it with the members as it might mean something to somebody and then they could share their findings here too. The Mills on the left ,with the pink filling band, came out of France and appears to be all original (as put together during the war components). It has a concave lever, brass filler plug, steel pin, unvented striker, and the cup type base plug marked; No.5. I. 5/16 and with the unattributed manufacturer marking of what looks to be a J I intertwined logo with LTD after that. Where the lever rests along the back of the body it is debossed verticaly on the 2 middle segments; L F. I'd always assumed this was a manufacturer's mark. Then I get the Mills on the right, which appears to have been together forever, (but possibly never filled), it has a pierced lever, aluminum filler plug, brass pin, vented striker and an aluminum plug marked: No5.1 / S.B.&CO (Seimens Bros) / 1916. Cast into the body the same way as the first but this time with the initials; Z F. Any ideas of what these marking might represent? The only other difference between the 2 is that the body of the LF has been finished better with the casting marks ground off smooth and the casting seams in the segment grooves ground away to leave nice sharp edges. The ZF is left more as it came out of the mold.