[Upgraded Smart Charger Controller] The smart charger controller built into the solar panel has six protection functions: over-temperature protection, prevention of reverse discharge, short circuit prevention, prevention of reverse polarity and over-charging protection. Meanwhile the built-in blocking diode plays an important role in blocking reverse current flow. [Real-time monitoring] The LED indicator has three display states, half lit means charging, blinking means fully charged, and off means no input or no battery connected. When fully charged, it will automatically cut off charging, effectively preventing the battery from being overcharged. [Stronger and More Durable]After rigorous testing, the A+ grade monocrystalline silicon wafers have a conversion efficiency of up to 23% to maintain a consistent output of 7.5W. The glass fibre surface is highly resistant to the environment, with IP64 waterproofing and UV protection. [Easy to Install and Use]The Outdoor Solar Battery Maintainer is simple to install and easy to use, just directly connect the solar panel to the battery with alligator clips. The solar panel is bendable to fit windscreens and has a strong hold on the 4 PVC suction cups it is equipped with. Also, it's easy to carry outdoor and restore on your car. Dimension: 9.84*8.66*0.47in, 0.05lb [Wide Application] The perfect charger/maintainer for any car, LiFePO₄, Lithium Ion, motorcycle, boat, tractor, ATV, farm equipment, and 12V batteries. ECO-WORTHY Upgrade 7.5W Solar Car Battery Charger Maintainer 12V Waterproof Solar Panel Portable Solar Trickle Charger for Car Truck Boat Lawn Mower RV Trailer Tractor Utility Vehicle Battery