By Waltham Precision Instruments. Clock, Aircraft, Mechanical Type A-13A-1. Part No. 400201. 1968 contract date. The case is approx. 6cm square and 4cm deep, manufactured in dust and moisture-proof aluminum and finished in a satin black colour. 8-day, 20 jewel keyless self starting movement. Black dial with luminous Arabic numerals and hands. Chapter ring marked in increments from 5 - 60 for the one-hour elapsed time feature. Pressing the upper right knob will start, stop and activate the flyback of second and minute hands. This does not disturb time of day. These clocks contain an unbreakable, anti-magnetic cobalt alloy mainspring and an anti-magnetic temperature compensated hairspring to ensure accuracy. All Waltham mechanical aircraft clocks are domestically produced and are certified to conform to FAR # 52.208-1. Excellent fully working condition. Quality precision clock. Stock code C19438.