The SS-6B-PRO is a 6-outlet power block with standard level surge suppression protection, EMI/RFI filtration, Extreme Voltage Shudown (EVS), heavy duty steel construction, and a 15ft. Power cord. The EVS provides over/under voltage protection and will automatically turn back on once the incoming power has stabilized. Another great value of the EVS circuit is that not only does it protect the connected equipment, the EVS also protects the SS-6B-PRO making a sacrificial situation highly unlikely.