Although energy bars are essential to any climber's nutrition, nothing gets you quite as fired up as dipping your mitts into Petzl's Power Crunch Box. Refill your chalk bag with this chunky magnesium carbonate, and revitalize your sweaty palms back to a proper dry state right before the crux. This nutritious balance to any boulderer's breakfast comes in tightly sealed box that won't leave the inside of your climbing pack completely white.