Granite Gear eVent Sil Drysacks

The eVent fabric on the bottom is waterproof but air-permeable. This allows you to squeeze the air out of the sack after you've sealed the top, effectively compressing your gear without needing a separate valve or complicated compression straps.

The main body of the sack is made from waterproof material, and the roll-top closure keeps water out. While the eVent bottom is designed to be air-permeable to allow for compression, it is also waterproof, meaning it will protect your gear from moisture while still letting air escape.

The block shape is designed to stack efficiently inside your backpack, eliminating the dead space that occurs when you pack round items together. This makes it much easier to organize your gear and maximize the internal volume of your pack.

Yes, the arched stay keeps the opening of the sack rigid and wide while you are loading it. This prevents the sack from collapsing on itself, making it significantly easier to stuff bulky items like sleeping bags or clothing inside.

It is generally better to store sleeping bags in a large, breathable cotton or mesh storage sack to maintain the loft of the insulation. These compression sacks are best used for transporting gear on the trail rather than long-term storage at home.