Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl)
When gear needs to get lighter and smaller, pack it into the Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl). Built from 30D diamond ripstop siliconized Cordura®, it weighs just 3.3 oz and squeezes a 20 liter load down to about 6.5 liters using four evenly spaced compression straps. The "Flip-Top-Lid" design keeps those straps from tangling every time you open the sack, and the slippery finish makes stuffing a sleeping bag far less of a fight.
Features
- "Flip-Top-Lid" design prevents strap tangling
- 30D diamond ripstop siliconized Cordura®
- Four straps for even compression with no bulging
- Extra-long straps so the sack can genuinely be filled to capacity
- Bar-tack reinforced stress points
- Webbing pull handle on the bottom
- Slippery finish for easy packing and extraction
- Supplied in assorted colors
Specifications
| Model |
Ultra-Sil Compression Sack – L (Large) |
| SKU |
stsultrasilcompsackl |
| Size |
9" x 20" |
| Weight |
3.3 oz |
| Volume (max / compressed) |
20 L / 6.5 L |
| Fabric |
30D diamond ripstop siliconized Cordura® |
| Compression |
4 straps with flip-top lid |
| Reinforcement |
Bar-tacked stress points |
Frequently Asked Questions
How much does the Sea to Summit Ultra-Sil Compression Sack L compress?
The Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl) takes a 20 liter load down to roughly 6.5 liters once all four straps are cinched — about a two-thirds reduction. It measures 9" x 20" uncompressed and weighs 3.3 oz.
Will a sleeping bag fit in the Sea to Summit Ultra-Sil Compression Sack L?
Yes. At 20 liters the Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl) is the size most people reach for with a three-season sleeping bag, a down jacket plus midlayers, or a full change of camp clothing. The extra-long straps mean you can actually fill it to capacity before compressing.
What is the difference between the Ultra-Sil and standard Sea to Summit Compression Sack?
Fabric and weight. The Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl) uses 30D diamond ripstop siliconized Cordura® and weighs 3.3 oz, while the standard Compression Sack line uses heavier 210D PU-coated nylon. Both use the same four-strap flip-top-lid compression system.
Is the Sea to Summit Ultra-Sil Compression Sack L waterproof?
No. The Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl) is a compression sack, not a dry sack — the siliconized fabric sheds light moisture but the seams are not taped and the closure is not a watertight roll top. For waterproof storage look at the Sea to Summit eVent or Ultra-Sil Dry Sack range.
What does the Flip-Top-Lid do on the Sea to Summit Ultra-Sil Compression Sack L?
On a conventional compression sack the four straps cross the opening and tangle every time you unpack. The Flip-Top-Lid on the Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl) anchors the straps to a hinged lid instead, so the mouth opens clean and the straps stay in order.
Where can I buy the Sea to Summit Ultra-Sil Compression Sack L?
You can buy the Sea to Summit Ultra-Sil Compression Sack L (stsultrasilcompsackl) at Going Gear, an authorized Sea to Summit dealer. Every sack ships new in original packaging with the full manufacturer warranty.
