Whether or not that toy is harness compatible will depend on the harness you are using. My Pink Candy minx doesn't work with that dildo because of the balls. The O ring is clipped on with three clasps, so the bottom clasps can't close right with the testicles. You are going to want a harness with four clasps instead.

Latigo leather Harness

If you are going to be using that dildo for multiple users be sure to use a condom. As that material is porous. Be prepared for that toy to stink like you wouldn't believe. Just like a shower curtain, pool raft, or anything like that. I'd recommend picking up a better material for a dildo. Silicone is completely non porous and can be thoroughly cleaned with a 10% bleach and 90% water solution, you can wash it in a dish washer, or you can boil it. PVC (what softee ballsy cock's material) can't be cleaned other then washing with soap and water. And it can have pours that harbor bacteria.
Silicone Realistic Dildos - Price is ranged low to high for you. And only those that are O ring compatible.