Model # YWF6E350-SHigh Speed Exhaust Fan 1,000 CFM, 14" Blade, 115V (Exhaust In)Totally enclosed motor with auto overload protection. Outside rotor motor for higher efficiency.Strong powder coated OSHA guardBlack powder coat maintenance free durable steel construction with outside rotor motor for high efficiency, complete with ETL certification.Swept back high efficiency low noise blade design.Quiet aluminum shutters to maximize airflowFan shipped completely assembledFraming Dimension 18" x 18"Efficient, low maintenance, easy to install.