A pair of brass fly buttons as used on R.A.F. and other British Forces battledress trousers etc. Designed by Christopher Clayton Hutton at MI9 and designated as the 'Swinger, Type No.6', one button has a small 'spike' in the centre on which the second magnetised button can be balanced. Small luminous dots on this button indicate North & South. Issued to aircrews to aid escape and evasion. This example is in mint unused condition, still attached to the card it was supplied on and with a tiny cork to protect the 'spike'. Stock code E26564.