Physical description
Cylinder shape a few scratches and showing wear and tear, Glass window with cream and green numbers. With black matt baked on paint.
Inscriptions & markings
Behind glass reads - GYRO HORIZON AMALGAMATED WIRELESS (A/SIA), MANUFACTURED UNDER LICENSE FROM THE SPERRY GYROSCOPE CO. LTD
Label reads - Serial No A.W.A /2739-, Part no 643720R, Patented Aust. 110675, 18.8.39, R.A.A.F. Ref no G6A/3330