This is a great example of the Conklin Word Guage fountain pen. The Nozac (meaning no ink sac) was first introduced in 1931 with a twist fill piston mechanism. In 1932, Conklin added the Word Guage Nozac with a transparent barrel section marked 1M-5M to indicate how much ink was left in the pen.
The clip is imprinted 'Conklin'. In addition to the word guage imprints on the barrel, the main imprint reads 'The Conklin Pen Co. Toledo. Ohio. USA. NOZAC D84394 Reg US Pat Off.' The nib is a generous medium 14k Conklin Cushion Point.
We have replaced the piston seal and the pen is filling fine. Condition wise, this is close to being unused with no significant marks, plating wear etc. The barrel has good transparency. Both cap and barrel have numerous micro scratches/marks from 80 years of storage. We could polish these off, but this would risk softening the imprints which are very clear and crisp, so best to leave it in its original condition (Ref 12234)