Panamax MFP-400 2 Outlet HD Ready Surge Protect - Black (Discontinued by Manufacturer) Premium Filtration Improves Picture and Sound. AVM (Automatic Voltage Monitoring) Universal Coaxial Protection Surge Protection 2 Outlets Improves picture and sound quality The MFP-400's Power Cleaning and Premium Filtration eliminates common symptoms of contaminated power Monitors incoming line voltage Panamax's patent-pending AVM circuitry continuously monitors the incoming line voltage and disconnects your equipment in the event of an over-voltage or under-voltage (brownout) Power is automatically reconnected when voltage returns to a safe level, eliminating service calls or system downtime