Thanks to its middle of the road 70 denier Nylon fabric, this drybag is durable enough for use in a kayak or canoe, while still remaining lighter than products made of tarpaulin-type materials. A great choice for protecting your apparel or sleeping bag. The structure does not feel a valve, as the bottom panel is made of air-permeable but waterproof eVent fabric. It lets air out as you compress the bag. The package contains one bag. The product image displays the bag both uncompressed and compressed. The volume refers to a closed, but uncompressed bag. The compression straps can bring the volume down to approx. 1/3 of the uncompressed volume. - Nylon material with 10 000 mm hydrostatic head, and sealed seams - Roll closure - PFC-free