For two-person big wall climbing, it pays to be smart with your gear. The Black Diamond Zion Haul Bag is about as smart as it gets. This big mother pig has a belay seat built in, and a burly padded hipbelt and shoulder straps that tuck away fast when they aren't useful anymore. The Zion's cavernous 145L interior holds sleeping, eating and summit celebrating gear for two people. The double-walled skirt makes it easy to get into, and sheds water so your gear stays dry if the weather sucks. If a big wall lies ahead, you'll want a big bag like the Zion.