As a dedicated backcountry hunter and backpacker, I’ve learned that a good night’s sleep is crucial on every hunting trip. For early season hunts, I usually carry a quilt for my sleep system but when the temperatures drop, I switch to a conventional sleeping bag for a draft-free night’s sleep. After testing the Sitka Gear HyperDown Sleeping Bag throughout the fall of 2023 and 2024, I’m here to share a few insights on unconventional design and its performance in the field.
Sitka Gear HyperDown Sleeping Bag Specifications
- Temperature Rating: 15°F comfort rating.
- Insulation: 900-fill power Allied ExpeDRY down
- Weight: 2 lbs. 3 oz
- Outer Fabric: 10D ripstop nylon
- Inner Fabric: 10D ripstop nylon
- Dimensions: 72″ long regular and 78” long tall
- Zipper: Center zip, 4/5th length, YKK snag-free zipper with full length baffle
For a more detailed measurement, see Mike Moore’s article, in which he compares the HyperDown bag to a similarly designed bag.
Design and Features
From the outset, the HyperDown bag with its center-zip and arm hole design is unconventional when compared to standard side-zip sleeping bags. The design allows for mobility around camp and in the field when extra insulation is needed over the clothing system, or nature calls in the middle of the night. The center zip allows for easy entry and exit of the bag, which can be especially helpful in tight camping situations, while the arm holes allow you to move your arms freely without fully exiting the bag.
This is particularly useful for tasks like prepping gear, getting dressed, or cooking. Engaging in these activities while still partially insulated in the bag, makes for more comfortable nights in the backcountry. There is a small hook and loop at the bottom of the bag that clips the foot box off the ground, which facilitates walking and donning boots. Very unconventional but very practical.
Sitka Hyperdown Weight
Weighing just a few ounces over 2 lbs., the bag is stuffed with 900-fill power down, offering an excellent warmth-to-weight ratio. The down from Allied is called ExpeDRY and is treated to be water-resistant, which helps prevent it from losing its loft when exposed to moisture. This is crucial for maintaining warmth in damp conditions, as traditional down can lose its insulating value when wet.
Fabrics
The outer and inner fabric is 10D ripstop nylon, which is very durable, breathable, and soft to the touch. There is a DWR applied to the fabric which is great for those nights when you might brush against the condensation in a damp shelter.
Size and Fit
The sleeping bag has a tapered design keeping the profile trim for weight savings yet allowing for movement while sleeping. It’s not overly constrictive, which is a common issue with many lightweight sleeping bags and a big reason I use quilts in the warmer months.
The hood of the Hyper Down sleeping bag has a unique design similar to the HyperDown Jacket, offering a contoured, adjustable fit to ensure heat retention around your head and neck during cold conditions. The footbox is roomy and large enough to accommodate extra clothes, a warm Nalgene, or even boot liners, which is a much-appreciated detail when the need to dry clothing arises.
Performance in the Field
The Sitka Gear HyperDown sleeping bag fits squarely in that “high-performance equipment” category—a serious piece of gear with a unique feature set, built to keep you comfortable in the mountains. Below is a breakdown of my experience with it and whether it earns its place in my sleep system in the future.
When it comes to warmth, the HyperDown bag excels. With a temperature rating of 15°F, I tested it in conditions as low as 12°F last November, and it performed as rated. The draft collar and adjustable hood are standout features, keeping warmth contained effectively. On cold nights, I was impressed at how well it retained heat, allowing me to wake up well rested and ready for the day.
Weight and Packability
Weight and pack space are king for backcountry hunters, and the HyperDown bag does well here. My test bag weighs slightly under the listed specs at 2 lbs. 1 ounce. This is light enough that I never hesitate to bring it on cold hunts where every ounce and cubic inch of pack space matters. The bag compresses well, minimizing bulk, which is particularly beneficial for late-season trips where pack space is at a premium due to other cold weather gear. The bag does not come with a stuff sack (but does come with a nice mesh storage bag) so factor in purchasing a quality sack for use with the bag. I use a Granite Gear compression sack that cinches the bag into a compact 8”x 9” ball and it takes up very little space when compared to other 15–20-degree bags I’ve owned.
Use of Features
Most sleeping bags use the classic side zip, but Sitka’s decision to go with a center zipper makes for a very useful feature. As mentioned above, entry and exit of the bag is easier when in a small shelter and convenient when nature calls. I found the zippered arm holes and hook and loop feature of the footbox to be excellent additions to the bag. I use the arm holes while operating my stove, eating, and sorting gear in my pack, without exposing my body to the cold. I’ve used it to glass from camp without leaving my bag, and it’s surprisingly comfortable to wear for extended periods as an extension of my clothing system. This really sets it apart from more traditional sleeping bags.
The two-way zipper itself is a smooth quality #5 YKK which didn’t experience any snagging or separation. There is stiffening tape applied on both side of the zipper to prevent fabric from bunching in the teeth, a very common issue with most sleeping bags. The zipper pulls are easy to find and operate even with gloves on. The long zipper allows for decent ventilation in milder weather or need to regulate your body temperature in the middle of the night. There is a baffle running the length of the zipper eliminating any drafts in that area. The arm holes have baffles as well, making the bag completely draft free.
The armholes zip smoothly and don’t let in drafts, so when you’re back inside the bag, it feels like a standard mummy bag. When fully zipped the hood effectively seals in heat around the neck without a draft collar and does not feel restrictive. There is a small inner pocket for storing small items like a phone, ear plugs or a small headlamp. I particularly appreciate how it keeps my phone warm and close so I can hear my alarm in the morning.
Durability
The bag is constructed of 10D ripstop nylon for the outer shell and inner lining, offering a solid balance between lightweight construction and resistance to tears or abrasions. I didn’t baby the bag during my outings—whether it was stuffed into a tight compression sack or pulled out on rocky ground, it held up well with no noticeable damage. The overall construction feels robust, and the bag has held up well under normal use. The stitching and construction are solid and I didn’t experience any issues with down leaking at the seams.
The DWR has diminished over time in the areas that are commonly exposed to body oils; mainly the head shoulder, and chest region. A gentle washing will most likely revive its water resistance as would a reapplication. The DWR is still performing like new on the other areas of the sleeping bag.
ExpeDry Down
The ExpeDRY down is unlike any other down I’ve used. It has maintained its loft after two seasons of repeated compressions, exposure to wet conditions, and plenty of body oil. There is zero loss of warmth and the bag quickly rebounds to its lofty shape after compression. The 900 fill down is premium in price but so is its performance.
Final Verdict
The Sitka Gear HyperDown Sleeping Bag has become a staple in my cold weather arsenal. Its lightweight construction, warmth, and outstanding durability make it an ideal choice for anyone wanting a premium feature-rich bag. It’s more than just a sleeping bag—it’s a tool designed to keep you more comfortable in the field longer. Using it as an extension of a clothing system adds to its value in certain circumstances.
For those willing to invest in premium gear, the performance, warmth, durability, and lightweight design should make this sleeping bag one to consider when looking to add to their sleep system. In the backcountry, the gear you carry can be the difference between a miserable trip and a successful one. Staying warm and comfortable at night can mean the difference between success or mentally giving up and going home. The HyperDown 15° sleeping bag checks all the boxes for those who need to thrive in cold mountain environments.
Price – $749.00
Comment or ask Josh questions here.
See more at Sitka’s website and read all our sleep system reviews here.
*Sitka Gear is a Rokslide advertiser.
