Designed for long-distance backpackers and outdoor adventure addicts, the SealLine Blocker Compression Cinch Sack is an ultra-compact companion for stuffing your sleeping bag, extra clothes, protective outerwear, or camping essentials. This particular cinch sack is water-resistant, meaning it'll keep your gear dry from passing showers and light splashes, but it's certainly not fully waterproof like comparable dry sack offerings. SealLine's Continuous Compression straps cinch tightly to minimize overall bulk inside your pack, but without exerting excessive pressure on seams that are prone to blowing out. The drawcord closure isn't as secure as a dry bag's roll-top, but it does offer quick retrieval and stashing of items on the trail when time is of the essence. Welded seams increase its durability, so you'll be able to use it for years to come. Plus, you'll find the flat-sided construction saves 20 percent in space when compared to circular-shaped sacks.