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Integral Designs' Silcoat Compression Stuff Sacks compress your sleeping bag so you can travel with a smaller pack, or a pack that is better balanced. The Silcoat Compression stuff sack will make a huge difference, extending comfort and reducing fatigue. Silcoat nylon is tough, water-resistant and very slippery, making it easier to slide a sleeping bag in and out. **If you're replacing a stuff sack, match the dimensions of your original sack to the dimensions by size indicated in the standard features list below.