For sale is a mens vintage Japan made Seiko "Bullhead" automatic wind chronograph wristwatch with dual date. The watch features a large stainless steel case with screw in back, black tachymeter non rotating bezel, original mineral glass crystal, original black & blue dial, one register for timing to 30 minutes, another register for timing to 12 hours, original black and white luminous hands, original yellow sweep center chronograph hand, original crown and round pushers and a Seiko stainless steel bracelet. The case reference/model number is 6138-0040. The movement caliber is 6138B (with 21 jewels).