Both used during urethral play, yet slightly different.
Penis plug users will wear the urethral plug during masturbation, thus providing sensations from the inside out. Some plugs can be solid and some hollow, such as the cum through plug = allowing liquids to pass through.
Urethral sounds are also inserted during penis sounding, they are usually longer and can reach the bladder - the most direct way to reach the prostate.
Please refer to our collection filter in order to choose the right one for you.