Elite-Air | FAT2 220 CFM Dual Fan Crawl Space Ventilator With Dehumidistat Specifications: Capacity 220 CFM Motors 115 Volts, with 50-60 Hz 2 Motors Included. The maximum Thermostat when On is at 50 F and Off is at 35 F. Dehumidistat: 20 80 RH Range. 8 power cord. Dimensions: 18" x 9" with 2" Face Plate Can Be Trimmed To Approx 14" x 6". Includes Thermostat To Prevent Operation Below 35 F. It will Return to operation At 50 F. The FAT2 plugs into a grounded electrical outlet. The Elite Aire FAT2 Crawl Space Ventilator is Designed To Circulate Fresh Outside Air Into Crawl Spaces under homes based on humidity levels.