A brass and copper US Navy Mark V diving helmet made by 'Diving Equipment & Supply Co Inc'  known as DESCO based in Milwaukee. USA. Dated October 1988 this helmet is in great condition. Four observation windows with guards, the front window hinged to one side, spitcock and a comms cup. Outlet to the lower left with wheel and banana valve, rear air inlet and telephone connectors and two breastplate eyes. A really good example.