To achieve higher power use requirements, this product can be stacked, such as: 4 grid inverter1000W stacking can achieve 4000W High Frequency 400W~600W Grid Tie Inverter A.System Function 1,directly connected to the solar panels (do not need to connect the battery)2,AC 0 angle with high precision auto-detection Pure Sine Wave Output3,Automatic Sensing Function Solar Luminosity Power ...