The Drilite Cap from Mountain Equipment is light enough to always have in your pack but provides breathable and waterproof protection when you need it.
Mountain Equipment says:
A lightweight and fully waterproof DRILITE® cap.
DRILITE - Shell fabrics featuring a monolithic polyurethane membrane that is waterproof, breathable and durable.
Mountain Equipment's Drilite Cap is light-weight, packable and waterproof cap. The lined headband provides comfort and wicks moisture away.
It has a pre-curved, stiffened peak which will enhance your field of vision and protect your face. The simple but effective Velcro strap allows you to easily adjust the size to suit. Mountain Equipment is a member of the Fair Wear Foundation meaning they are committed to giving factory workers safe, dignified and properly paid employment.