The ends of our cable are marked “IN” and “OUT”. IN=Source, the side with the IN goes to the player or video source (Blue-Ray, etc.).
The booster cable is not recommended for installation inside walls, it is more advisable to put a “passive” cable inside the wall and have the booster as a separate item. Please see our ADP5130 or ADP5133 for a stand-alone model or our WDH681001 for a wall mount insert.
Also please note that some new HDMI displays have booster circuits built into them making the external booster unnecessary.
(Variation SKUs M5133A-100 and M5133A-75)