In 1944 Lt Col A. T. C. Priddle, of the directorate of Tank Design, was certain that he could design a better compass than the Compass Department and this is the result. A small compass with a 0.5" (1.3cm) card is mounted at the top of a 27" (68.6cm) Bakelite tube while at the bottom is a prism box in which it was to be viewed. A corrector box around the tube takes 2.5" (6.4cm) corrector magnets. This "walking stick" compass was supposed to be thrust out of the top of the tank when required and dropped into a shoe. The weight of the prism box caused the fragile tube to break. Also the compass could only be used in full daylight, to be used when stationary and was vulnerable to attack.