Restoration Hardware WWII 8 Day Clock Inspired by a real 1940s World War II aircraft clock, our exacting reproduction - enlarged to three times the original's size - faithfully echoes every detail of the 8-day clock, with four mounting screws, luminous hands and numerals, and a large knob at the bottom for winding and setting the time (its larger size making it easier for gloved pilots to grasp). The bottom dial, originally used to display elapsed time, is decorative.