Prospex Speedtimer Solar Chronograph. Designed for those who treat life as the ultimate adventure, Seiko Prospex keeps moving forward, meeting every challenge with technological excellence and winning design. This dramatic watch is part of a high-intensity collection inspired by the 1969 "Speedtimer," the world's first self-winding chronograph, extending it to the Black Series. Featuring Seiko’s "Green LumiBrite Pro," developed by combining the color most recognizable in the dark with a higher brightness and longer afterglow, this extraordinary timepiece provides a "night vision" experience for visibility in the dark resembling the view seen through a night scope. The chronograph function measures up to 60 minutes of elapsed time in 1/5-second increments and includes a split time function, while the solar cell, powered by any light source, with no battery change required, provides a 6-month power reserve when fully charged. The dark gray dial features 3 black subdials, and includes a 24-hour indicator and power reserve indicator, as well as a date calendar and green LumiBrite hands and markers. Crafted of stainless steel with black hard coating, curved anti-reflective sapphire crystal, black tachymeter bezel, and a secure screwdown caseback black nylon strap. 10 bar, 100M Water Resistant