Set the duration and speed with the remote control from as far away as 45 feet then hold on as the fan spools up to draw a massive 1400 CFM through the 5 micron primary filter and then through the 1 micron secondary filter. Changes the air in a 20" x 20" x 8" room 26 times an hour. Hangs easily from the ceiling. Three pocket internal filter bag simplifies cleaning. Dimensions 30-1/8" x 19-7/8" x 16-3/8" weighs 73-Pound We have a limited supply of stock that is CSA certified. Please call 1-800-523-4777 for more details as these are available upon request only. Shipping exceptions may apply.