solar system 1. Easy use and installation 2. DC and AC output ... AC systemFor home application, whole set(solar panels, battery, inverter, controller), output form 400W-8KW, easy installation and use.ModelLYDS-20WLYDS ... cloudy2-3 days2 days2-3 daysGuarantee1 year1 year1 year solar system(DC20W-50W)