Scrotal implants are stainless steel, nylon, or other beads or objects implanted inside the scrotum.
Generally a doctor does this procedure as it is quite invasive and carries a considerable degree of risk. However, on a technical level, the procedure is within the grasp of a competent amateur practitioner. The largest risk is infection, which can occur even years after the implant is done. This risk is greatly increased with heavy implants such as large steel beads, and is greatly minimized by using medical-grade implants. Neuticles are available through veterinary suppliers.