Oxy Shop Urethral Sounds KitThe Rosebud Urethral Sounds Kit is a collection of medical grade steel urethral sounds. They are designed like rosebuds, to gently insert into the urethra and stretch it with time. Each of these sounds is about 9. 3 inches long, and their thickness varies. The 5 piece set starts at 0. 23 inches going to 0. 39 inches. KEY BENEFITS using a penis plug: Great feelings and unique sensations: If feels like nothing else. An orgasm from the inside out.