For sale an extremely rare and special CITIZEN CRYSTRON 4 MEGA (Cal.7370D) high-accuracy (±5 seconds per year), high-frequency (4.19MHz) quartz watch in pristine condition with its original Citizen watchbox and sale tag! This watch was manufactured in October, 1979 in Japan. It features the famous 4.19MHz (4,194,304Hz) high-frequency quartz movement (Cal.7370D) to achieve accuracy within ±5 seconds per year!!! This watch is a collector's item as it is extremely rare and unique especially in this pristine condition! Here are the factory specifications: - Movement: Citizen Cal.7370D - high-accuracy (±5 seconds per year) high-frequency (4.19MHz) quartz - Date: quick set day-date (selectable: English or Japanese) - Case and bracelet material: stainless steel - Dial size: approximately 35mm (without the crown) - Water resistant for everyday use - Battery life: approximately 2 years - Made in Japan! The bracelet is full-size so the watch fits even a large wrist (approximately 22cm). I'll send the pdf file of the Technical Manual (Cal.7370D) to the buyer via email. The watch is in pristine original condition (see the included pictures) with the original Citizen watchbox and sale tag! The watch performs within the factory specifications