It would need an old work electrical box or an old work non electrical box installed in order for the screws to hold and it be secure. The non electrical old work box is basically a plastic frame that installs behind the drywall and has screw holes to receive the screws from this HDMI receptacle. This is very inexpensive and is what I used and would recommend.
My 3D Samsung TV does not have a COAX input, only HDMI, and I want to use this to connect an external antenna (via COAX to HDMI). I don't see anything other than this plate that may be able to do this conversion. Is it possible to loop the HDMI to the COAX (since all of the external antennas come with standard COAX connectors)? I want to drop my cable company's box, but don't want to give up my awesome TV.
This plate saved me from having to put another hole in my wall. I just replaced the existing box that had the Cat5 and ran an HDMI down to the this plate. I have heard about the coupler not passing thorough picture but this can be solved with removing the existing one and pulling the HDMI further through if it is cause a problem. So far I cant tell a difference in picture between one HDMI cable or through the coupler.
Great wall plates, used them for my home theater setup. Keep in mind that distance between the concrete wall and your drywall has to be enough to hold the HDMI entry, plus the actual HDMI cable. I'm thinking of using an angled (90 degree) adapter, to compensate for this. Other than that, delivery was reasonable, and the quality seems reliable. Would definitely recommend.
Recessed Combo Wall Plate for RJ45, Coxial, and HDMI Cables
This wall plate was just what I was looking for. The only problem, though it is a general problem with HDMI Cables, is that there is no way to lock them into the connector on the wall plate. So it is possible that the cable will not work if the cable is not fully connected to the adapter. It would be nice if there was a way to lock HDMI cables to their connector.