The Outdoor Research Ultralight is a featherweight bag designed to provide an added layer of protection against foul weather from inside your backpacking pack. Made of 40D ripstop with a polyurethane coating, this roll-top bag weighs a mere 1.8oz. While Outdoor Research succeeded in creating a lightweight bag, it failed to produce one that provides significant protection from water. This model was the lowest scoring product in 3 of the four categories we tested. Most notably, the material of the bag itself absorbed water during testing, and our testing towel was left a soggy mess.Wet clothes, and even worse, a wet sleeping bag while backpacking puts a serious damper on a trip. The Osprey Ultralight is also made of thin, lightweight material but was significantly better at repelling water and provides a good option for storing clothes. The is a must buy for backpackers and won our Top Pick for Sleeping Bag Stuff Sack. It has the ideal design for storing your sleeping bag or down jacket and is exceptionally waterproof.
Outdoor Research Ultralight Dry Sack Review
Cons: Absorbs water
Manufacturer: Outdoor Research
Our Analysis and Test Results
The Outdoor Research Ultralight is made of 100% polyester 40D ripstop with a polyurethane coating. The 20L size measures 20.5-inches long and has a 9-inch diameter. Weighing in at only 1.8oz, this model is a super light version of the classic roll-top dry bag. Unfortunately, it took last-place amongst its competitors with particularly low scores across the board.
Waterproofness is the most important aspect of these products. After all, they are specifically intended to keep your things dry. Unfortunately for the Ultralight, this metric was its undoing. Not only did everything get wet during our testing, but the material of the bag itself absorbed water.
The Osprey Ultralight offers a similarly designed product but fared significantly better in this category. If you are looking for something similar in size that provides greater protection from water, the Sea to Summit Big River is worth considering.
Ease of Use
The Ultralight is shaped like a cylinder with a flat bottom. Unlike the which has the same cylindrical shape, the material of the Ultralight is too flimsy to hold its shape while packing.
This model has a simple construction. It closes with a standard roll-top, but the lip is reinforced with plastic to help give it shape for rolling. There is a single D-ring at the lip, but with just poor waterproofness and thin material, this model belongs inside another bag, and thus we can't imagine needing something more hefty to secure it with.
The Sea To Summit eVent Compression, on the other hand, is a backpacking specific model that took home a top score in this metric. Its eVent allows for easy compression while at the same time preventing water from seeping in.
Reduced weight means a thin material that is prone to tearing. This model definitely belongs inside an outer pack with minimal exposure to rough surfaces. This is the one metric, however, that this model didn't come in the last place. The Osprey Ultralight sustained a small tear, whereas the Ultralight held up to the same use.
Weather is hard to predict in the high country and whether you are hiking in the Sierras or the Andes, being prepared for rain is prudent. The Ultralight provides a thin layer of protection for your clothes just in case the rain makes it through your shell and inside your pack.
For sleeping bags or down jackets, the Sea to Summit eVent Compression is a better alternative for its compressibility and its superior waterproofness. If you are looking for a more rugged model that can stand on its own and is entirely waterproof, check out the Watershed Colorado Duffel.
A price tag of $25.50 makes this an inexpensive model, but for a few dollars less you can get the Osprey Ultralight which provides a similar gossamer bag but is also significantly more waterproof.
We liked the idea of this ultralight product, but other models, like the Osprey Ultralight did better with the execution.
— Leslie Yedor
Ad-free. Influence-free. Powered by Testing.
GearLab is founded on the principle of honest, objective, reviews. Our experts test thousands of products each year using thoughtful test plans that bring out key performance differences between competing products. And, to assure complete independence, we buy all the products we test ourselves. No cherry-picked units sent by manufacturers. No sponsored content. No ads. Just real, honest, side-by-side testing and comparison.Learn More