Amorphous solar panels are lightweight, versatile and hard working. These panels will produce even on overcast days! Use these panels for smaller battery charging such as automotive, quad, fish finders, auxiliary batteries. Can be permanently mounted or temporarily mounted using the accessories included. 2W solar panel measures 8" by 5" and weighs less than 2 lbs. Keeps a battery topped up. Use with cars or power sports vehicles such as quads that are used only occasional or have weak batteries. This item does not require a solar charge controller.