British WW2 Escape compass ‘singer’ type variient as issued to allied pilots, paratroopers, commandos, the regular army and SOE agents as part of escape and evasion kits.
British Escape compass, ‘swinger’ type consisting of a small magnetised strip of diamond-shaped steel sheet 8mm x 30mm with with a central threaded hole with non-ferrous screw-in mount with central small hole to through with to feed thread.
To use it, you would tie it to a string and let it float in water to get your bearings. British paratroopers had this type of compass sewn into their battle dress for Operation Market Garden and these compasses were well suited for concealment inside small everyday objects such as shirt collars and hems off skirts. Examples are also known to have been moulded into plastic combs.