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 and scratching to main casings. Covers/caps absent. Dirty and slightly corroded internally. Remarkably difficult to find now. Stock code H12186.