Strong and durable construction. Revolutionary Gaseous Tritium Light Source (GTLS) Technology produces bright illumination that keeps its brilliance for ten years or more, and it's always on-doesn't require "charging" from an external light source. The MX20 has an stainless steel case, triple-coated sapphire crystal, and your choice of polymer band or PVD stainless steel bracelet. Double O-ring sealed and waterproof to 660 ft.
