Reliable and efficient, Detmar blowers offer the highest capacities available. Detmar's specially designed five-blade, bullet-nosed impeller and cambered stator vanes provide extra high pressure with a minimum of turbulence. Housings are molded of tough, corrosion-proof plastic with rugged built-in mounting brackets for easy installation and quieter operation. UL listed. Three-year warranty. 4" In-Line Blower - 240 cfm open flow. 5-3/4" L x 4-3/4" H.