The problem is that you never see it coming on the Diamond. One moment you're climbing vertical, east-facing granite at 13,000 feet. The next you're staring at heavy, dark clouds boiling over the summit from the west. Seconds later, lightning cracks. The Alpine Houdini has an ultralight 100% nylon ripstop shell with a DWR (durable water repellent) finish and a waterproof/breathable membrane that serves the simplicity crucial to alpine rock climbing , and its afternoon thunderstorms. It's emergency rainwear for climbing that also blocks wind, traps your heat on chilly belay ledges, packs into a single internal chest pocket (with clip-in loop) and seals up with elastic wrist cuffs and a single-pull drawcord waist. With helmet-compatible, single-pull adjustable hood.