As the basis for underwater time reading, all Shijin custom stainless steel diving watches are equipped with eye-catching luminescent hands and scales. Usually, the hands, scales, or dials of dive watches are coated with luminescent materials, and the size of the hands and scales are deliberately enlarged to make reading the time easier for divers. The early luminescent material was radium, which was discontinued because it contained excessive radioactive elements. The most commonly used luminous material for custom dive watches now is Super-LumiNova, which absorbs gamma particles in the light and can last for more than 10 hours (but the intensity of the light will decay after a certain period).