Original U.S. Navy WWII Large N288s-27405 Summer Flight Helmet by Slote & Klein with Goggles & Earphones Lewis Gun New Made Item: These are

New Made Item: These are excellent high quality Canvas

so we cannot determine accurately the manufacture date

There are however some burrs on the tumbler

which is the early Hartford style:

By December of 1936

Original U.S. Navy WWII Large N288s-27405 Summer Flight Helmet by Slote & Klein with Goggles & Earphones Lewis Gun New Made Item: These areOriginal Items: Only One Set Available. This is a very nice flight helmet set, which was exactly what Aviators of the U. S. Navy used during WWII. The helmet is a very nice khaki tan canvas "summer weight" style, and has a nice chamois lined "visor" and ear cups. The chin strap is still intact, though unfortunately the buckle on the other side was removed at some point. It still has the original maker label at the rear: SIZE LARGE CONTRACT No. N288s