I have a set of rosebud sounds measuring from 5mm to 12mm obtained on e-bay of all places! My girlfriend can insert up to 9mm with plenty of lube and a bit of discomfort to my pee-hole opening. I have seen pics of much bigger sounds inserted, but don't know how my urethral opening can be stretched without some serious damage being done! I guess this is supposed to be done over a period of time with progressive sizes, but am at a bit of a loss how this is achieved - any ideas?