Whether you want to keep your kit dry or just compress your gear for better packability these compression bags and stuff sacks should be just what you're looking for. You'll find great solutions to help you protect your kit with products from great brands such as Exped, Equinox and Outdoor Research.
Equinox Bilby Nylon Mesh Stuff Bag - 11 x 16 146360
Equinox Mesh Stuff Bag - 15 x 22 146365
Equinox Bilby Nylon Stuff Sack - 5 in x 8 in 146313