4 PORT CABLE TV / HDTV / DIGITAL AMPLIFIER INTERNET MODEM SIGNAL BOOSTER INTERNET AMP 4 ports with a signal boost of +7 db per port. Improves cable modem performance in many cases.Compatible with all cable TV systems. Will reduce cable pixelation and graininess due to low signal levels. Coaxial cables not included. 6 kV surge protection for lightning strikes. Gold-plated, berylluim copper construction, and powder coated housing deters corrosion. 5-year warranty when purchased from an Authorized PCT Distributor/Dealer. Warranty not valid when purchased through other outlets.