Seiko 5 Sports x Automatic ft. SKX Series Men Formal Round 100m Water Resistant Watch SRPD55K1 SRPD55 SRPD-55 SRPD-55K1 Explore the Seiko 5KX Sports - a modern evolution of the iconic SKX with 4R36 automatic movement, display case back, and drilled lugs for easy strap changes. This 13.5mm-thick, 46mm lug-to-lug watch keeps Seiko DNA while offering bold dial options and LumiBrite lume. A versatile, affordable mechanical timepiece for all styles. Caliber Number / Movement 4R36 (automatic with manual winding capacity) Power Reserve / Accuracy Approximately 41 hours (+45 to -35 seconds per day) Crystal Hardlex crystal Luminous LumiBrite on hands and indexes Case / Band Material Stainless steel case with stainless steel band (three-fold clasp with secure lock, push-button release) Water Resistance 100m / 10 bar Case Size Thickness: 13.4 mm Diameter: 42.5 mm Length: 46.0 mm Lug width: 22.0 mm Other Specifications Seiko 5 Sports x Automatic ft. SKX Series Magnetic resistance (4,800 A/m) Undirectional rotating bezel See-through case back Screw case back 24 jewels Day and date display Stop second hand function (hacking mechanism) Regular timekeeping (analog display)