Seiko 5 Sports x Automatic ft. Field GMT Series aka Khaki Drill Men Formal Round 100m Water Resistant Watch HDB001K1 HDB001 HDB-001 HDB-001K1 Seiko 5 Sports Field GMT HDB001 Khaki Drill, a compact 39.4mm stainless steel case with a curved hardlex crystal. Powered by the in-house automatic caliber 4R34 with a 41-hour power reserve, hacking seconds, and a 24-hour GMT hand for dual-time zone tracking. The green dial features large Arabic numerals and LumiBrite for low-light legibility. Caliber Number / Movement 4R34 (automatic with manual winding capacity) Power Reserve / Accuracy Approximately 41 hours (+45 to -35 seconds per day) Crystal Hardlex crystal (curved) 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: 13.6 mm Diameter: 39.4 mm Length: 47.9 mm Lug width: 20.0 mm Other Specifications Seiko 5 Sports x Automatic ft. Field GMT Series aka Khaki Drill Magnetic resistance (4,800 A/m) See-through case back Screw case back 24 jewels Date and 24-hour (GMT dual time) display Stop second hand function (hacking mechanism) Regular timekeeping (analog display)