This dual power automatic transfer switch is PC level, household power transfer switch. When the normal city power is abnormal, the back up power works at once, no Interrupt, ensures the continuirty, reliability, and safety of powersupply. Features: Solid structure, reliable conversion, convenient installation and maintenance, and long service time. Compact size, suitable for most household distribution box. Automatic power, switching time less than 10ms. Manual/automatic 2 modes, switch at will. Made of fine quality PC material for safer use and long using time. Ensures the continuirty, reliability, and safety of powersupply. Specifications: Type: 2P, 4P (optional) Rated working current: 63A, 100A, 125A (optional) Material: PC Main color: black+white Package size: 2P: 112 * 103 * 82mm / 4.4 * 4.1 * 3.2in 4P: 146 * 103 * 82mm / 5.7 * 4.1 * 3.2in Package weight: 2P: 560g / 1.2lb 4P: 750g / 1.7lb Packing List: 1 * Automatic Transfer Switch