Cut off the end of your extension chord leaving at least two inches of wire length from the power circuit or plug end of your cord. Because were only making an in wall extension cord there isnt any reason to turn off the power.

Commercial Electric In Wall Power Cord And Cable Kit A32 Kw The Home Depot
Running tv power cord through wall. This cut lets you move the wire through the wall without having to make a large hole to fit plugs or power strips through the wall. This way you have the best of both worlds. If you ran the tv cord through the wall there must be an outlet receptacle nearby. Might be safe as can be but i wouldnt do it. To be code compliant you must use a power transfer kit like what is shown here or simply have a licensed electrician install an ac outlet behind your tv. Youre supposed to have a new electric socket installed directly behind the tv where you can plug in.
Hiding the cord while remaining within code and not having any future problems. In a nutshell it allows you to run 120v through the wall without needing to run the wires along a stud. In other words it makes it easy and safe to run your power cable. If so you can add a receptacle rather easily behind the tv. The installation was very straight forward and simple to follow. It was around 60 and well worth the price tag.
4 it is actually an electrical code violation to pull the tv power cord through the wall. This is the perfect solution to have the aesthetics you want in your home and being sure that your family is safe. Even low voltage speaker wire that isnt in wall rated is a no no. Running anything with power other than in wall rated power wire romex in the wall is against code and will void your home owners insurance iirc if a fire were to occur. In other words running power cords through the walls is not a substitute for permanent wiring. These cables will heat up more than most other cables.
It is perfectly safe to run most cables through a wall. Ok so are you ready for the tutorial. The cord can later be reattached once it is routed through the wall. They can cause electrical fires if there is a cut or another issue with the cable or device. Really the only cable you absolutely should not run through a wall is a standard power cable that plugs into an outlet. Feed the wires through the retro fit single gang box and then screw in the screws to secure them.
At the time i didnt know that running your tvs power cable inside the wall is not up to fire code. Cut two holes place the unit in the wall and run the cable.