Grape Solar's 400 W (4 x 100 W) off-grid kit is made for RV, pumping or other off-grid operations. The included solar panels come with an anodized aluminum frame and a waterproof, sealed junction box. The panels feature 2-diode bypass for minimizing the power drop caused by shades. The Xantrex 35 A PWM charge controller can support system expansion up to 400 W with the addition of 2 new 100 W panels. Also included is an 1800 W Grape Solar pure sine wave inverter with 2 outlets and 1 USB port for your AC power needs. The inverter can power up demanding electrical loads such as variable speed power tools, advanced electrical appliances, microwaves and more. In addition, the inverter provides power to the most USB chargeable devices via the built-in USB port.