RAF issue Aircraft Clock, Mk 2C
28. The clock Mk. IIC has a self-starting 8-day movement and has been introduced as a replacement, in some instances, of the clocks Mks. III, IIIA, and IIIB. When fitted in place of a clock Mk. III, IIIA or IIIB and using the same fixing holes, an adaptor plate is required. This clock is similar to the clock Mk.IIB with the exception that the hand setting is effected by pulling out the winding knob instead of pushing it in, also it has no dummy hand features.