I think what you are referring to is when someone says they are fishing over tree tops or brush tops. You would not see it , as it will be weighted to the bottom. A lot of people make their own, by lashing cut limbs together and weighting them down, marking the coordinates. Toledo Bend is full of them, but you have to have a good fish finder and understand what you are looking at, to find them. As Vic said go to the electronics forum and that may help.
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