Check the listing for details. NEW RadonAway Model RP145 (RP145c) 4" Radon Mitigation Fan/Pump 23030-1. Condition: New. Listed at 149.00 USD. RP series fans. This group is primarily used with high flow situations. This includes drain tile, gravel or where settling has occurred beneath the floor. The RP145 fan can handle a wide range of situations. It is designed to move large quantities of air with drain tile systems or gravel but also able to produce a maximum of 2.1WC for tighter sub soils. If you can do 2 suction points with tight soils this fan will provide good results with minimal energy usage. Energy efficient at only 37-71 watts Super quiet operation ELT Listed - for indoor and outdoor use Meets all electrical codes Commercial and residential Thermally protected motor 4" inlet and outlet Note: Utility cords need to be purchased separately. The RP145 has 4" openings thus requiring either 4"x4" or 3"x4" rubber couplings for mounting. When in doubt 4" pipe is recommended for the RP145.