Stores reference 10A/7063. 'Receivers, telephone, head, type C', as used with the Type B flying helmet and Type D oxygen mask. Manufactured in plastic/bakelite moulded over a steel shell with a separate screw-on bakelite cover. Surface wear, scratching and knocks to main casings. Both covers/caps are absent but the internal components appear to be largely complete. Dirty with some corrosion on the case threads. Remarkably difficult to find now. Stock code H13018.