The Transpack XT1 Boot Bag has the same Isosceles Storage System that you love but with a slightly bigger volume and a few extra compartments Zippered mesh pockets on the outside of the boot compartments add extra storage and an internal zippered pocket separates important personal items from all of the gear The extra durable fabric is definitely airline worthy and its water resistant too to keep the contents dry 600 denier polyester fabric is extra durable Isosceles Storage System with separate pockets for each boot Center pockets keeps helmet goggles clothing etc away from snowy boots Water resistant fabric keeps the contents dry Tarpaulin bottom easily wipes clean Zippered mesh side pockets for extra storage Internal zippered pocket for important items Neoprene padded backpack straps for easy carry Volume 2800 cubic inches / 46L