I like them too. My shoulders are not the best and these felt OK.
It is actually a T-bar attachment that has enough range of motion to do overhead stuff. Basically a plate that screws to the wall, a bracket with a tube to hold the end of the bar. It came with the other stuff I bought. I have seen the overheads done with the end of the bar jammed in the corner.
I need to get a V-handle so i can do T-bar rows.