HQRP 50 Watt (50W) Solar Electric Power Panel. The solar cells are encapsulated beneath high transmission tempered glass. The rear surface of the module is completely sealed from moisture and mechanical damage. Construction of the module minimizes weight while providing a durable, protective environment for the solar cells. Considering the fact that solar panels are supplied with MC connector, You will need to buy aditionally cable adapter (not included into the set). HQRP UV Chain / UV Radiation Tester: To know the Solar UV Index, it is enough to compare the colorchange with the 4 standard colors around. Very light purple: low intensity, UV index 1-2. Sun-protection not necessary. Light purple: medium intensity, UV index 3-5. Sun-protection is recommended. Purple: strong intensity, UV index 6-7. Sun-protection is necessary. Dark purple: very strong intensity, UV index 8-11. This tester shows you the level of UV radiation and helps you protect your eyes and skin from negative sunlight effect, but this meter doesn’t show sunlight intensity for solar panels.