e) DURABLE & SAFE: Made with corrosion resistant stainless steel blades, steel wire guards, iron shell with anti-rust coating, provide longevity to the fan. Thickened protective dense mesh design can both prevent fragment from being involved to the motor blades, and also prevent accidental touch injury EFFICIENTLY: With light weight pure copper motor, it provides continuous and quiet ventilation. The backdraft damper of the exhaust fan can contaminated air to flow out of the home but prevents air from sweeping back in to the home EASY INSTALLATION: Can easily be added to a window opening or opening in the wall along with a thermostat to optimize cooling. We have installed the spare wires inside the motor, that you can connect the wires yourself without our plug APPLICATIONS: Eliminate heat, moisture, odor, and dust. Allow speedy reduction of humidity levels. Applied to kitchen, bathroom, toilets, bedroom, living room, shopping mall, and office AFTER-SALES SERVICE: Welcome to ask about use and function, we will give you a fast reply within 24 hours (working days)