Mil-Spec, or Military Specification, denotes the standards set by the U.S. Department of Defence for sourcing, fabrication, materials, quality, and supply. A product meeting these criteria can be called a Mil-Spec item or component. The Luminox 3350 Series watch adheres to the MIL-PRF-46374G performance standards, ensuring that its water resistance, durability, and overall quality align with the requirements of the U.S. Department of Defence. - Swiss Quartz - Approximately 84-month battery life - Constant glow for up to 25 Years - 46mm Case Size - Stainless Steel Case - Rubber Strap - 14mm Case Thickness - Sapphire Crystal - 300 Meters Water Resistant *Additional Strap & Tool