Bought one of those for the wife and I. It just goes over the shaft. It has a small vibrator built in above the shaft. It also has a small tickler wrapped around the vibrator that hits her clitoris. It was amazing. She was freaking from the feeling. I thought I was going to explode, but did not. The built in cock ring was amazing. We went at it for a couple of hours. All sorts of positions. Then she made me take it off as she had several orgasms and was ready for me to unload. I took it off and lasted another 30 minutes. Those things are amazing. Now she almost begs me to have sex.
I felt one that pulled the balls up would cause the boys to get in the way.