Generac RXSW100A3 100 Amp 120/240V Single Phase NEMA 3R Service Rated Automatic Transfer Switch for Standby Generators Generac Automatic Transfer Switches are designed for use with single phase generators that utilize an Evolution or Nexus Controller. This 100 Amp open transition switch is available in single phase with service equipment rated configuration and works in tandem with the generator to monitor the utility power. When utility power is interrupted, the transfer switch automatically transfers power from the utility to the generator. When utility power returns, the transfer switch will return the electrical load from the generator back to utility. Through the use of digital power technology (DPM), these switches have the capability to manage up to 4 individual HVAC (24 VAC controlled) loads with no additional hardware. Generac manufactures the widest range of power products in the marketplace including portable, residential, commercial and industrial generators. At Generac, we protect the things that power your life by providing quality, affordable power solutions. This model replaces model RTSW100A3. Features 100-Amp 120/240 volt single phase Smart transfer switch with service disconnect which is housed in an aluminum NEMA/UL type 3R enclosure with electrostatically applied and baked powder paint Transfer switch connects through the utility meter for easy installation; smaller fuses integrated into the control board Heavy duty Generac contactor is a UL recognized Device designed for years of service The controller at the generator handles all the timing, sensing, exercising functions and transfer commands Can be used in Tandem with Generac's Smart Management modules, up to 8 more loads can be managed as well, providing the most installation efficient power Management options available USA SHIPPING estimates delivery times and we work to get your item to you as quickly as possible and within those times, but please know it may take slightly longer than the estimate.