A completely new concept in compression dry bags - there is no valve. This innovation uses an air-permeable base made of eVent waterproof fabric, which allows air to be pushed out of the sack, but won't allow water to get back in. Suitable to keep contents dry in any wet situation where the bag is not submerged. Unique compression idea - allows air to be pushed out to compress, but water can't get in because of the waterproof, air permeable eVent fabric base Rugged 70 D nylon body & lid Waterproof seams - double stitched and tape sealed Roll top Hypalon closure with lid and 4 straps evenly compresses and maintains compressed size Reinforced stitching on all stress points Pull handle on the bottom Super compact and very light See product care for tips on washing, repairing and getting the best from your gear Proper Use: Any roll-top dry sack must be closed properly to ensure water can't get in. Begin by folding the Hypalon strip down first and be sure to have at least three rolls before closing the buckle. Avoid contact with sharp objects or subjecting the sack to high abrasion, as this could compromise the waterproof fabric. Like all manufacturers of roll-top, fabric dry sacks, Sea to Summit recommends that sensitive electronic devices be "double bagged" (i.e. putting electronics inside one dry sack then placing this inside a second dry sack). For maximum protection, the use of a waterproof hard case should be considered. Not intended for situations where dry sack will be submerged under water.