Automatic Transfer Switch, Voltage 208, Phase 3, NEMA Enclosure Type 3R, Max. Wattage 20,000, Load Transition Type Open, Standard Installation, Max. Amps 100, Height 24 1/8 in, Width 20 1/8 in, Depth 7 in, Enclosure Material Aluminum, 2-Wire Start No, Warranty 2 yr, Automatic Exerciser No, Gray