A bit of color on a gray day. Tissot T12 Electronic cal430 divers watch. NO: It is not a quartz. Swinging at 28800ah the ESA Dynatron does away with the mainspring by use of a battery/magnet circuit. At 44mm diameter wo crowns it must be one of the bigger three handed watches of that time (Early 1970's). Original Gay Freres bracelet adds to the charm.