Mr. Gray's response makes sense---but I still prefer my four-point harness (
Terra Firma], discontinued here but still available elsewhere) for a dildo with balls. The snaps can obviously travel around the O-ring so you can situate them in the way that's most comfortable. I've found with my three-pointed Jag that it can kind of mash the balls up, and not necessarily always exactly where I want them to be. Plus, they're not visible that way.