Electroline EDA400 Compact Bi-Directional Signal Booster 4-Port Cable Modem TV HDTV Amplifier with Passive Return SIGNAL BOOSTER DROPAMP: 4 Ports with a +7dB boost per port, boosts your signal strength 15x. PROTECTION: 6 kV surge protection on all outputs EXPECTED RESULTS: will improve HDTV reception. Reduces snow and prevents image pixelation with digital cable. Your experience may vary based on the quality cable TV or antenna input signal. Compatible with all cable TV services and over-the-air antenna signals. Used by your major Network Provider such as COMCAST, SPRINT, AT&T, VERIZON, etc 5-year warranty when purchased from an Authorized Channel Master Distributor/Dealer. (Amazon Prime customers let us know)