G.A.S Enviro V2 Fan ControllerG. A. S Enviro V2 Fan Controller Precise Control Over Your Grow Room Climate The G. A. S Enviro V2 Fan Controller is one of the best ways to manage your grow room environment. It gives you full control over your intake and extraction fans, helping you maintain the perfect temperature and humidity all year round without constant manual adjustments. If youre running serious lighting or growing through the summer, this controller will help keep your