British WWI 'PH' Tube Helmet

The PH helmet is of gray flannelette with gray flannel interior lining, fitted with screw-in metal bezel and glass eye pieces as was used for the second pattern Hypo helmet.  A metal tube exhalation valve is attached with a rubber tube valve on the interior of the helmet, and the helmet is stenciled at the base "PH 27" and marked in several places with a maker stamp "L.LOTTERY & CO."  The tube valve fitting has the rubber exhalation valve, though it is rigid and fragile; lacks the rubber portion on the interior.  Exterior has stains and discolorations.  The eye pieces have rusted and suffered significant material loss from that oxidation, and the surrounding fabric is heavily stained here it wasfolded over the rusting eye pieces.  Lacks satchel.

The PH helmet is outwardly similar to the P helmet, but with the addition of hexamine to the phenolate and glycerin solution, yielding greater resistance to phosgene gas and some limited protection against hydrocyanic acid.  The PH superseded the P helmet in early 1916 and remained in use until replaced by the small box respirator later that same year.  $1500 - $2000