If you're into sounding (something known as catheter play or urethral dilation), you'll already know that it's not something anyone should go into without lots of prior research, time, patience and a great set of high quality tools. These are those tools.
Sounding is the act of involves inserting a rod or plug up through the penis via the urethral canal. For some, it provides a completely unique sensation and lots of pleasure, since the head of the penis and urethral canal is jam-packed with nerve endings. Sounding is also used as a means to direct prostate stimulation, while some penis-owners get off on the extreme nature of sounding. In either case, it's not something to be done on a whim, so if you're interested, please do your research!
In body safe stainless steel, the five included sounds are naturally extremely firm and quite weighty. Each Sound is identical in shape - there's a slight angle to each tip and lots of arrow-straight length in between. The smallest rod measures in at .16"/4mm at widest and the largest is .47"/12mm. There are three sizes in between, so you'll easily be able to find one that suits your need, desire or experience level.
Always follow a meticulous cleansing routine before and after using one of these (or any) urethral penetration deice. The stainless steel construction of each included Sound ensures extra through cleaning - boil them or bleach them for reliable sterilization. Always use the highest quality lube with any tool that'll be entering our or your partner's urethra - the best option is a sterile surgical or medical grade water based formula.