The ACF 314 and ACF 328 simultaneously cool up to three avionics units. Operating on 14Vdc and 28 Vdc respectively the ACF 314 and ACF 328 supply up to 20 cubic feet of cooling air per minute, helping maintain your avionics at a proper operating temperature. SANDIA Aerospace cooling fans use high quality, brushless blower motors and or RunQuiet technology. These units are FAA PMA and have passed stringent environmental testing to ensure years of reliable service.