Unless they've changed the design a lot, they're wrong. I'd call mine weather resistant at best. It sure as HECK isn't anything like waterproof. The Cateye TL-LD1xxx series is waterproof, maybe some of the others I haven't tried. I don't think even the Hotshot is actually waterproof - just water resistant, and only really weather resistant, as the charging socket would let water in if it was submerged.