ECO-WORTHY 200 Watts 2pcs 100 Watt Polycrystalline Solar Panel 12 Volt Battery Charging for RV Boat High module conversion efficiency. Ideal output: 1KWh per day (depending on the availability of sunlight). 100 watt is the ideal output, the actually output is less than 100w for all the 100w solar panels. If the panel output is less than 80w with sufficient sunlight, please feel free to contact us, we will be responsible for it. Pre-drilled holes on the back of the panel allow for fast mounting and securing. Anti-reflective, high transparency, low iron-tempered glass with enhanced stiffness and impact resistance, Withstand high winds (2400 Pa) and snow loads (5400 Pa). Two panels could be connected in parallel to be 12v or connected in series for 24v system.