citizen jet auto dater para water ar51407061 1960sAuto Dater is the CITIZENs first automatic watch with a date function revealed in Jan 1962. The Jet was the thinnest self winding mechanism developed in Japan at the time. It is said to have been named with the reason the sound of winding is like a jet engine. The name Auto Dater is a combination of Automatic and Dater. Para Water is the first complete water resistance mechanism in Japan, which is water resistant up to 40 meters by embedding special