Astronergy CHSM60M-HC-370W Bi-facial solar panel meaning it can absorb sunlight from the top and bottom of the solar panel, increasing the output by up to 30% (depending on what the light reflected off). The series has monocrystalline half cut solar cells which increases the power density and shade resilience. The front side has a 20.2% efficiency rate, and the back has a 14.2% efficiency rate for reflected light.