Despite its impressive dimensions, this pillow is quite light weight, as it belongs to the manufacturer's Ultralight series- especially considering how much the pillow significantly affects sleeping comfort, it's easy to recommend even to hikers who are concerned about weight. The valve is as advanced as those on sleeping pads: it does not let air escape between breaths, but on the other hand, allows for quick deflation when it's time. - Compatible with the Pillow Lock Velcro strips that come with Sea to Summit sleeping pads: the pillow does not slip on the pad when you install the holders and slap the pillow onto the pad - 20 denier polyester fabric - The baffle structure helps keep the head in place - Includes a lightweight packing bag