The Skye Instruments SKA 400 Apollo Light Meter is a hand-held device that was specifically designed to allow easy readings of UV light sensors, allowing accurate measure of harmful UV rays. It can store configurations up to six different sensors an read from other voltage output sensors. This allows easy, instantaneous readings from skye ultraviolet sensors, including UV-A, UV-B and UV-I (Erythemal curve). Apollo has over two lines on its LCD display that make it easy to see the readings, as well as its units.