Maximum Testicular Implants Size?

I was wondering if it would be possible to get really large Testicular Implants, i mean like small breast implant large. I have not seen any implants that I am happy with in size. I was also wondering if it would be possible to get a type of expander implants for Testicular Implants. I really want to know, I would like to drastically enlarge said area and would like to do so without resorting to dangerous means. Thank You for your time.