This B+W UV-PRO Premium device uses UV light to kill bacterias that cause lens fungus and is now available in Leica M mount (can be used for cameras and lenses). Here is a short video demonstrating how it works: Check pricing and availability on Amazon, eBay and DigitalRev (currently available only for Nikon and Canon mounts). More pictures … Continue reading This B+W UV-PRO Premium device should prevent lens fungus (Leica mount compatible)