For monster alpine routes, trimming your gear to the bare essentials requires calculations. But it aint rocket surgery (fortunately), and our M10 Jacket tidily solves the equation. Its the lightest 3-layer waterproof/breathable shell we make; and the soft, pliable, newly updated H2No Performance Standard nylon ripstop fabric yields surprising durability for its weight while protecting against monsoon-season precip and summit ridge gusts. New low-profile handwarmer pockets sit above harness line and complement the single exterior zippered chest pocket that doubles as a stuffsack (with reinforced clip-in loop). Details include sonically welded seams with the narrowest possible tape, watertight zippers, a microfleece-lined neck and chin, and cuffs that adjust with ultraminimalist hook-and-loop closures. A single pull adjusts the helmet-compatible hood (with laminated visor and simplified cord-and-hook stow design), and a drawcord hem blocks out spindrift backdraft.