Height & True Airspeed Computor MK.IV. By The London Name Plate Manufacturing Co. Ltd. Stores reference 6B/345. Circular white metal instrument, approximately 15cm diameter. Has rotating discs for setting altitude, airspeed and so on. Used by Navigators when plotting routes etc. In excellent unused/unissued condition with box of issue having October 1951 packaging date. Box worn. Believed early postwar use. Stock code M17686.