I clean all my Spartan/Huntsman Lites in an ultrasonic cleaner, submerged for 30-60min in soapy water. There's really nothing to damage. These knives don't have circuit boards with sensitive components like the Altimiter/Voyager/Traveller knives do, it's just an LED, some wire and batteries. Pull the batteries, clean with a much water and soap as it takes to get the gunk out, let dry and you'll be fine.