Southwire 40100001 50A Automatic Transfer SwitchTransfers to generator power automatically when energized after 30 second delay. When both shore power and generator power are available, generator dominates after a 30 second delay. Once the generator is shut down, shore power activates after a 3 4 second delay. Proprietary electrical interlock Time delay at power up Dual contactor arrangement Does NOT provide surge protection UPC: 024098401006 Model Number: 40100 001