The AirPair is the yin-yang of stuffsacks. Socks on one side, underwear on the other. Hat on one side, gloves on the other. Dried fruit on one side, nuts on the other, lots of possibilities. Made with 30D sil-nylon CORDURA so they're tough and ultralight. Micro cord and cordlock, hypalon grommet, fully finished seams. All the quality and features you've come to expect from Granite Gear. The Bloc shape is an innovation to help you pack more efficiently inside your pack. Compared to a round shape, the bloc fits better into the corners of your pack, they stack nicely, and eliminate all the "dead air" that can happen when you try to pack with round stuffsacks. Less dead air means better load stability, quicker pack loading, and the possibility of carrying the same amount of gear in a smaller pack, saving you weight.