&####127464;&####127462; Canadian Respirator, Anti-Gas, Mk. V dated May 1942 by the BF Goodrich Company size Normal. V General Service Respirator was developed in 1939 by the United Kingdom as an improvement of the Mk. IV General Service Respirator which removed the layer of Stockinette over the mask which made the mask cheaper to produce in a war torn economy. V GSR features either a Stockinette-covered or a non-Stockinette-covered rubber hose connected to a plethora of filters, this being a Type E Mk. IV dated 1942 by the Toronto Macdonald Plant, a Mk. V Valve Guard, Mk. III B Eyepieces (Unofficial Designation), and a No. III Head harness by Kaufman dated February 1942. The carrier to the Canadian Mk. V would be the Mk. Va, Mk. Vi, or Mk. ViI, with this example being a VII dated 1943.