Customize your foldable Plixi helmet for any kind of weather that's thrown at you. The cover makes the helmet more waterproof and is easily removable in hot weather to let your helmet breathe. You can also leave it on the helmet when you fold it. It's like the Plixi has it's own umbrella. Available in two sizes to match your helmet. What's it made of?Stretchy waterproof fabric.  How does it come?In a plastic sleeve.