Noted: There are no any Button Control for our products. Bathroom Exhaust Mount Hole SIZE - Please note the size of the housing is 10 x 10 inch, resizing your existing ceiling opening will be needed if your current fan housing is smaller HIGH-QUALITY VERSATILE FAN： Quiet, energy efficient exhaust fan operates with 110 CFM and 1.2Sones to help control air quality is powerful enough for rooms (including bathroom) up to 105 sq-ft. Duct Diameter 4 inch INSTALLATION - Torsion springs grille mounting - no tools necessary for a quick and easy installation. Compact housing fits easily between ceiling joists，No Attic Access Required. EFFICIENT: Powerful ventilation reduces to quickly eliminate fogged mirrors at 110 CFM, so your vision will always be clear and your surroundings will always be comfortable RELIABLE PERFORMANCE: Detachable 4 inch polymeric duct with back draft prevention damper.Nalle Vent fans reduce air leakage by up to 50% compared to competitive models, resulting in better home performance via blower door tests and reducing cold and warm air backdrafts Innovative Design:

All new grille designs that will compliment any decor.

Efficient Operation:

Plug-in, permanently lubricated motor in a compact housing.

Easy Installation:

Retrofit installations can be done entirely from the room-side.

4-Inch Connector:

Polymeric connector with tapered sleeve and no metallic clatter.

And all with new grille designs that are at home in any decor.

Innovations include foldable mounting ears and new damper and housing technology that improve building airtightness like never before.