My Rotary is MY go to light when I'm headed out anywhere that is potentially dusty, grimey, or otherwise icky. I certaintly don't want to expose just any light to some of the adventures I have when on holiday , in the car hole, or geocaching. Only my Rotary is trusted for such important times. And, so far, I have had NO issues with dirt, dust, sand, or other elements getting into the Rotary dial. When my light has gotten icky and it needs a bath, I've run it under the water and used a little Dawn dishsoap (if available) and have given it a bath. Good as new. Rotary dial . . . fine. The light still works as well as the first day I got it.