The Kinky Kat runs on 1 AA battery and is surprisingly strong for it. There are a total of 10 functions that are all activated with the button on the base of the shaft. One press gets you a high setting, then medium, low, a series of pulses, different pulsing, another pulsing setting, quicker pulses, slower pulses, longer pulses, short low pulses, then back to high again. You can turn the toy off by pressing and holding the button for 2 seconds, which is convenient if you happen to be walked in on. The vibrations themselves aren't anything extraordinary; a bit buzzy but still pretty strong. They're also quiet enough that even on high you shouldn't be able to hear them underneath a blanket or from the other side of a closed door.
There is an o-ring where the battery cap meets the rest of the shaft that worked well in the shower, but fully submerge at your own risk.