8 In. automatic wall fan features a permanently lubricated motor, steel housing, and polymeric fan blade. Built-in damper minimizes back-drafts. Built-in rotary on/off switch. 11-1/2 In. square white polymeric grille can be painted to match surrounding walls. Adjustable housing fits walls from 4-1/2 In. to 9-1/2 In. thick. 14-1/4 In. square outside flange. 180 CFM (cubic feet per minute). UL (Underwriter's Laboratories) listed.