Pack Stuffers are heavy duty Sil Cordura pack-shaped zippsacks that are designed to match the cross-sectional shape of your backpack. Finally, a packing system that fits perfectly inside your pack; there"s no room for load shifting and no dead air space. There are 3 sizes of Pack Stuffers. The large is the base layer, and goes on te bottom of your pack. The medium fits in the middle and the small fits as the top layer. Our Bear Hugs are heavy duty Sil Cordura bear canister shaped zippsacks. Bear Hugs slide in your pack to fill the voids on each side of your bear canister; where bears are present. Bear canisters system are typically a "bear" to pack, and the Bear Hugs tames the process.