There is an adapter that goes on the tripod so the camera can be rotated from vertical to horizontal around the lens axis.
I've had one since I bought it new but it was only recently, after using my RB67, that Ive started using it. The drawback is its a bit heavy and there isn't a quick release. It does have pins for the camera and works flawlessly.
I've had my camera for a long time, bought it new, and have always enjoyed using it. I have a WLF and a metered prism finder.
For years all I used was the waist level finder. I've got a bunch of lenses. I was surprised how good the 105-210 ULD zoom is. I'm not a zoom advocate but it's very handy. My 80mm is the sharpest I believe.