BNC video splitter, also called a BNC T connector, splits BNC video in to two. You can use this to split the signal from your security camera or DVR in two. Simply place this adapter on the video source and connect your regular CCTV BNC cables to run the video signals. Experience has taught us that you cannot run the split video signal longer than 300ft without the use of a video amplifier Balun. This is for use with analog security cameras that are non-HD resolution.