A small indicator light is a small indicator that indicates that electrical equipment is operating. There are products such as short body types in which the operation unit and the contact unit are integrated, contact separation types in which the contact unit can be added or replaced, and both types are used by inserting them into the mounting holes of the device. LED lamp products are the most common, but there are also products that use incandescent, neon light sources, etc. In most cases, the shape of the glove part is rounded, round, or square. The main colors of the lights are red, green, blue, yellow, etc., and some products illuminate in multiple colors. Main applications are electronic and electrical equipment, measuring instruments, industrial and machine tools, switchboards, etc. In addition to the products used in the facilities, there are small indicator lights with increased luminance so that they can be easily checked outdoors or in daylight.