I've recently become custodian of this blue plastic(?) 10-sided button filler, and thought I'd run it past the forum on the off-chance that anyone knew anything about it. It's clearly of lower quality - there are voids in the surface of the barrel where the white has not mixed in sufficiently with the blue, for instance, and the pressure bar is one micron away from being tin foil - but it has a certain charm. 134mm capped 121mm uncapped 156mm posted 11.5mm barrel diameter (flat to flat) Translucent yellow button and ink window, the latter marked "4". (Mould number, I assume?) Nib is steel, tipping worn to a decided foot, ebonite feed. The only identification on it is the nib, and yes, I appreciate that may mean nothing, but it's all there is. It's not terribly clear, so pardon for inflicting an "artist" rendering of it in case it helps. To me it looks like mountains...? Anyway, any suggestions, pointers, wild stabs in the dark, reminiscences over how awful the one you had was, etc, all welcomed. Thanks, Al