This is an exceptionally rare Westinghouse manufactured M1 helmet liner and one of just two surviving examples that I know of - this one being in far better condition than the other. Westinghouse received a contract for high pressure M1 helmet liners on February 28, 1942 and was the first supplier to make deliveries by May 1942. The earliest liners had stationary, non-removable leather liner straps and rayon suspensions retained by rectangular washers. It is generally understood that the next production variation saw the introduction of A-washers, followed by studs for the removable leather liner straps. This example, however skipped over A-washers and showcases the new, removable leather liner strap. In fact, neither Helmets of the ETO nor The M1 Helmet of the World War II GI mention this liner's existence. The liner's original rayon suspension is strong and intact; it is held in place by rectangular anodized aluminum washers. It has recently been completed with an original flat-buckled leather liner strap, size 4 rayon neckband, and a size 7 1/8 rayon headband. The exterior retains its original olive drab factory finish. This rare liner would display quite nicely when paired with a mid-1942 fixed loop shell.