This is for one 25 Watt Solar Panel. It can be mounted on either a curved or flat surface or it can be suspended in air. 

17.8 Volts (Ideal for charging 12 Volt Battery systems). 

This should be connected to a charge controller for optimal trickle charging of a single deep cycle or starting battery.

This is a great addition to your winter storage plans.

(photo shows 50 watt panel, this is for style illustration purposes only, actual panel has less number of solar cells)