1More compatibility with a variety of storage batteries such as VRLA battery, gelled electrolyte (GEL) Battery, 2V x 2 iron-phosphate-based lithium batteries 2V x 4 iron-phosphate-based lithium batteries, 7V x 1 iron-phosphate-based lithium battery.2Prevent storage battery being overcharged, over discharged and back discharged at night and it also has PWM charging protection.3Automatically turn on floodlight according to the lightness at sunset. Regularly turn off floodlight according to the set value or automatically turn off according to the lightness at sunrise. 9 grades can be adjusting for the controlling light sensitivi4Open circuit is used for anti-overcharge protection, which effectively protects solar panel.5Automatically memorize various parameters set by the users, and the data will not lose in the situation of unexpected power failure or the battery power is used up.