Marathon General Purpose Mechanical Wristwatch w/Tritium GPM Stainless Steel. These Men's Watches from Marathon have tubes of tritium on the dial hour hand and minute hand for dependable softly glowing illumination all the time. The Marathon Watch GPM Dual Winding Wristwatch can be wound manually or rely on automatic winding from the motion of your hand while you wear it. Designed for infantry wear in the field the Marathon Watch GPM Illuminated Tritium Watch is ideal for everyday wear and outdoor adventures. Specifications for Marathon General Purpose Mechanical Wristwatch w/Tritium GPM: Manufacturer: Marathon Application: Military Gender: Male Dial Color: Black Case Finish: Stainless Steel Band/Strap Material: Nylon Wrist Band Type: Strap Water Resistant Mark: 164 ft Age Group: Adults Features of Marathon General Purpose Wrist Watch w/Tritium Illumination GPM: Dual-wind mechanical movement. Manual winding or self-winding rotor. When automatic watch winding system operates there is a mechanical noise and the rotor can be felt oscillating verifying that the system is performing as intended. Runs about 41 hours when fully wound. Sapphire crystal is 3mm thick ensuring scratch resistance legibility durability and impact resistance. Self illuminated 24/7 tritium gas tubes on minute hand hour hand and at each hour position on dial last for up to 25 years. Hour positions indicate both military time and standard time. Lightweight durable nylon strap. Fibershell high impact case with stainless steel back. Swiss made authentic military watch. Package Contents: Marathon General Purpose Mechanical Dual-Winding Watch w/Tritium GPM Marathon WW194003SS-0001: General Purpose Mechanical Wristwatch w/Tritium GPM Stainless Steel