Sea to Summit Ultra-Sil Dry Sack
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- Made from 30D high-tenacity Cordura siliconized nylon
- Waterproof welded seams with roll-top closure system
- Ultra-lightweight construction for minimal pack weight
- Available in multiple sizes from 1L to 35L
- Compression-capable design to reduce bulk
- Reinforced base for added durability
- Bright interior color for easy content visibility
Tech Specs
Pros
- Extremely lightweight for its volume capacity
- Highly packable and compresses down small
- Genuinely waterproof when rolled correctly
- Wide range of sizes for different gear needs
- Durable despite thin fabric construction
- Bright colors make finding items in a pack easier
Cons
- Thin fabric can be punctured by sharp objects
- Not fully submersible for extended periods
- Higher price point compared to basic dry bags
- No exterior pocket or attachment loop on smaller sizes
- Roll-top requires multiple folds for full waterproofing
The Sea to Summit Ultra-Sil Dry Sack is a featherweight storage solution built for backpackers, hikers, and campers who count every gram in their pack. Constructed from 30D Cordura laminate siliconized nylon, this dry sack manages to be remarkably tough while weighing next to nothing, making it a favorite among thru-hikers and minimalist adventurers who still refuse to compromise on protecting their gear. The roll-top closure creates a watertight seal that keeps sleeping bags, spare clothing, electronics, or food supplies safe from rain, splashes, and even accidental submersion during river crossings or unexpected downpours on the trail. Beyond its impressive water resistance, the Ultra-Sil Dry Sack is designed with practical organization in mind. Available in multiple sizes and a range of colors, it allows outdoor enthusiasts to color-code their packing system, separating wet gear from dry, or quickly identifying which sack holds cooking supplies versus clothing without having to dig through an entire backpack. The included compression capability lets users squeeze out excess air, reducing bulk and helping gear fit more efficiently into tight backpacking spaces, which is especially valuable on multi-day trips where every inch of pack space matters. Durability is a hallmark of this dry sack, as the siliconized fabric resists abrasion from rocky trails, rough campsite surfaces, and the general wear and tear of frequent outdoor use. The seams are taped to reinforce the waterproof barrier, ensuring that even after repeated exposure to moisture, mud, and dust, the sack continues to perform reliably trip after trip. For campers and hikers seeking a dependable, lightweight, and long-lasting way to keep their gear dry, organized, and protected, the Sea to Summit Ultra-Sil Dry Sack remains a trusted staple in outdoor storage solutions.
Customer reviews
I use the 13L size for my sleeping bag and it keeps everything bone dry even during multi-day rain. The weight savings compared to my old dry bag is noticeable on long trails.
Works exactly as advertised for waterproofing, but I did get a small puncture from a tent stake stored inside. Just pack smart and it's fantastic.
I bought three different sizes for clothes, electronics, and food. The color coding helps me find things instantly without digging through my whole pack.
Held up well during a rainy backpacking trip in the Pacific Northwest. Only minor gripe is the price, but the quality justifies it over time.
I was skeptical about how small this could pack, but it's incredible. Barely takes up any room in my pack when empty, yet holds a surprising amount of gear.
