SUNAPEX 20 Watt Solar Car Battery Charger 12 Volt Waterproof Solar Powered Battery Charger & Maintainer 12v Solar Trickle Charger for Car Boat RV Marine Trailer Battery 20W solar battery charger is made of more effective monocrystalline silicon material, which absorbs solar radiation heat to a greater extent. The power generated is at least 30% higher than other solar panel chargers, which greatly improves the charging efficiency and speed.
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