It is supposed to waterproof, but our Chinese friends can be a bit sloppy at work. In all the LCDs that I've seen full of water, the water went in where the cable comes out, so maybe put a bit of butyl bath sealant around the cable to double seal it. You can also protect it with a freezer bag and rubber band. i'd definitely do that if you're going to leave your bike out in the rain all day.