This is a unique model that uses a UTC disc hand that displays UTC time on a subdial at 6 o'clock. The number on the ring at 6 o'clock tells you the approximate time in cities in the Northern Hemisphere. The UTC disk needle slowly makes one revolution during the day. Fonts often seen on old maps and aviation charts are used to represent each city and number on the disc, giving it an intellectual touch from the 1600s as the world evolved. By intentionally using a different font from the aviation slide rule section, we also aimed for readability. The dial and bezel are enlarged for improved visibility, and the case is mortar-shaped to reduce weight and emphasize thinness. It has a matte finish that accentuates the hairline, and the bezel slope and button guards are finished with a mirror finish, giving the design a crisp look. The back cover is engraved with a map of the Northern Hemisphere.