Hi everyone, a friend asked me to try 'n repair a couple of old pens, originally belonging to his grandfather. There are two parker and a sheaffer, but I can handle those. The kicker is the fourth pen: It's a black, faded to brown waterman with a 2 written on the nib and a 72 written on the butt of the pen. I must say I've never heard of a 72. So I'm asking you for some information before I continue. 1) Does this exist, or is what I think is a 7 actually a faded 1 ? 2) When was it produced ? 3) What's the working mechanism ? (If it's a safety, I'm sending it off for repairs) 4) Any tips, tricks or warnings in restoring this ? Thanks in advance, M.