Why do You Need a GRECELL 12V 25W Solar Battery Charger Maintainer? -- Power Up Life Anytime Anywhere! Over time batteries naturally lose power, if allowed to, can go flat completely, even if it is fully charged again, the maximum capacity of the battery will be reduced; the battery life will also be reduced if the battery is not used and charged for a long time. 12V battery whose voltage is not kept above 12.4V has the possibility of sulfation, which is the main reason for the failure of many batteries and why the auto battery easy goes to dead when vehicles are left standing for long periods. GRECELL 25W Solar Battery Trickle Charger Maintainer will help you maintain a healthy battery by converting solar energy into a usable 12V DC current to keep your battery topped off at a stable level and extend the life of the battery, never be caught flat throughout the year segment! The solar charger is a basic of trickle charger and it is best for slowly charging and maintaining battery charge. It is the essential component for your 12V battery charging Off-Grid System and suitable for keeping vehicles/boat battery charged during the weeks unused. No need to disconnect the battery or have someone start the vehicle periodically. It is better for battery maintenance of small size vehicle. Convenient Plug & Play Come with 2 piece SAE cable kits, plug and play, easy to use. No electricity cost, free maintenance for outdoor use. Easy to install with pre-drilled holes on the back of panels for fast mounting and securing. Comes with carabiner and suction cup to meet your different installation needs. Suitable for automobiles, RVs, motorcycles, ships,snowmobile, etc. On-the-Go Solar Battery Charger The shape is lighter and thinner, and it is easy to use. The attachment hook makes it ideal for connecting to your backpack while hiking or walking around town, ensuring a smooth user experience. IP65 Waterproof IP65 waterproof and spark-proof, withstand rain and snow, the battery is fully protected. The rugged design can withstand high winds (2400Pa), hail and snow load (5400Pa). Please not allow the controller on the back of the panel to be submerged in water for a long time. Advanced ETFE Lamination The ETFE-laminated case is durable enough to extend a double life-span of the solar panel compared to other PET solar panels. The panel doesn't need film protection anymore. We added a layer of PCB as the bottom plate. An extra layer of bottom plate will make this solar panel stronger. Using thicker wires will make it more durable. Versatile Compatibility Coming with a SAE to car cigarette lighter cable and a alligator clip cable, you can also buy a SAE to O-Ring terminal cable(not included), the 25W solar battery charger can maintain most mainstream 12V rechargeable batteries like LiFePO₄, Lithium Ion, AGM, SLA, GEL, EFB, MF batteries, etc,. It is also a perfect solar power kit for variety of off grid applications like shed, cabin, gate opener, etc where 12V batteries is used, as well as to charge and maintain AGM, Flooded, GEL, Deep Cycle and Seal Lead Acid, etc batteries in car, Rv, boat, marine, trailer, camper, pump etc. How to Use? 1、The cigarette lighter cable is used to connect to a vehicle's 12-volt power outlet. Certain brands of cars do not have electricity after they are turned off, it can‘t be used normally. It is recommended to use alligator clips or O-rings for connection. Note:You must disconnect the charger from your cigarette lighter or battery when starting you engine or driving. Electrical surges from the car engine when starting and running may damage your charger. 2、The alligator clip cable is used to quickly connect the battery. It is not recommended to use it while the car is driving, it may cause a short circuit due to looseness. Note:Ensure the red cable is connected to the positive (+) and the black cable is connected to the negative (-). Do not leave the solar charger connected and unattended for long periods. 3、The O-ring cable (not included) can be connected to the car battery for a long time.If you do not need frequent disassembly and connection, you can choose this method. Kindly Note: Solar Battery Trickle Charger Maintains the 12V Battery of Car, Truck, Marine , Motorcycles , Tractors, Atvs, Snowmobiles, Boat or RV 1、It is a trickle charger that keeps the voltage from dropping or recharging the battery, but it is not a fast charger and cannot charge a dead battery. Please use the AC charger to fully charge the battery before using the solar panel. This solar charger can't store electricity. 2、If the battery capacity is 20Ah or greater, the charger will not overcharge the battery or cause any damage. 3、The suction cups can be installed forwards and backwards for fixing inside and outside of the car glass, placing the charger in the desired location in direct sunlight. Note:Some vehicles have tinted windows that will seriously affect the performance of your charger if it is positioned behind them. For Optimum charging the unit should be placed outside the vehicle in direct sunlight! 4、Clean the Solar Battery Charger MONTHLY, or more frequently to maintain peak efficiency.