For a long time, the pricing of Chinese cotton sleeping bags and tents has been in an abnormal market. Foreign-brand cotton sleeping bags retail for 700–800 yuan or even over 1,000 yuan, while Chinese cotton sleeping bags typically cost around 200–300 yuan, with better ones not exceeding 400 yuan. On Taobao, some so-called mummy sleeping bags rated for sub-zero temperatures can even be bought for just a few dozen yuan. Are foreign brands really that profitable?
Recently, I spent over a year visiting six or seven well-known fiber cotton companies, including 3M, THERMOLITE, and THERMORE, discussing and researching the fabrics and manufacturing processes of foreign brands like TNF, MHW, and SD with professionals. I also repeatedly calculated the costs of the KAILAS cotton sleeping bags I oversee. I felt it was time to write a dedicated article to clear up some misconceptions.
For most Chinese hikers, buying a cotton sleeping bag is usually determined by two factors: the temperature rating they see and the salesperson’s recommendation. Few actually analyze and choose for themselves.
First, choosing based on the temperature rating you see—how accurate is it? Do you know how domestic brands determine their sleeping bag ratings? Have they tested the clo value or thermal insulation rate in a lab? As far as I know, most domestic sleeping bag ratings are based on the gram weight of the cotton filling, then referenced against the ratings of similar foreign cotton sleeping bags. This leads to a problem: is the cotton used the same? Is the fabric the same? If not, the rating is definitely inaccurate. I’ll go into more detail about cotton later, but different fabrics also affect warmth retention.
Second, the salesperson’s recommendation. This is easy to understand. In an outdoor store, there are usually only two or three brands of cotton sleeping bags for sale. The salesperson can only recommend what their store carries, and whether it’s good or why—it’s likely they can’t explain either.
The temperature rating itself is actually a pretty tangled issue for me. Usually, abroad, the clo value is tested first, then a complex formula is used to calculate the rating. There’s also testing for thermal insulation rate, which can be used to calculate the clo value, and then the rating. By then, my head is spinning—I confess, I’ve never done these calculations myself. They’re just too headache-inducing, so I always have someone else do them.
Now, about cotton. Current fiber cotton mainly falls into a few categories: hollow cotton, spiral spring-like support, and multi-layer stacking... In short, the goal is to fluff up the cotton to trap air layers and achieve warmth. The one that’s lightest, fluffiest, and most supportive makes the best sleeping bag.
Hollow cotton, a product developed by DuPont but now sold to Invista, creates hollow fibers to trap air. Many domestic no-name cotton manufacturers claim their cotton is hollow, but it’s actually imitations of THERMOLITE.
Multi-layer stacking—after selling hollow cotton to Invista, DuPont developed this type of cotton, but due to its high price, it’s rarely seen in the market. Domestic brands don’t even bother, as the cotton cost alone would scare off most retailers.
Spiral-style is easy to understand—cotton is shaped like a spring, naturally fluffing up when released to provide support.
Besides shape, there’s also the feel of the cotton. Often, the fluffier the cotton, the rougher it feels, making it less comfortable to sleep on. But the softer-feeling cotton often doesn’t have great fluffiness. It’s a Hamlet-like dilemma.
One thing to note: not all fiber cotton needs high fluffiness. That’s mainly for cotton sleeping bags. Some cotton, like 3M’s Thinsulate, is designed for clothing, so most of its products prioritize warmth while being lightweight and thin (thinness for aesthetics), unlike sleeping bags that require lightness and fluffiness. Washability also differs—clothing cotton usually has higher washability requirements than sleeping bag cotton.
Last week, after visiting two fiber cotton processing plants, I suddenly realized that all the fiber cotton used in our current cotton sleeping bags is vacuum-compressed during transport to reduce volume. This process causes a 15–20% loss in fluffiness. I plan to use non-vacuum-compressed cotton for KAILAS sleeping bags, which will offer much better fluffiness and warmth retention at the same gram weight. The only issue is that the sleeping bag factory must be right next to the cotton factory—otherwise, no one can afford the shipping costs (I think this is why no brand uses non-vacuum-compressed cotton).
Enough talk—let’s look at pricing. Below is a cost breakdown comparison between a typical domestic cotton sleeping bag and a foreign-brand one. To avoid bias, I won’t name specific brands or models. I’ll just explain a cotton sleeping bag with a similar 0°C rating. The domestic version retails for 200–300 yuan, while the foreign brand costs around 1,000 yuan.
1. Fabric—this is the biggest cost component of a sleeping bag. A standard mummy-shaped sleeping bag requires 4 yards of outer fabric and 4 yards of inner fabric, totaling 8 yards. Often, good sleeping bag fabric costs 3–5 times more than cheap fabric, and this difference makes up a large portion of the total cost—sometimes even more than the entire cost of a low-end sleeping bag.
2. Cotton—the material cost varies greatly. Some cheap domestic cotton sleeping bags use cotton that costs only one-tenth of THERMOLITE. When I used THERMOLITE cotton for a sleeping bag, the cost nearly gave me a headache for two days. Of course, THERMOLITE isn’t the most expensive cotton—just more expensive than that.
3. Zippers—though a sleeping bag only has one zipper, usually just over a meter long, the cost difference between a no-name zipper and a YKK zipper is several times.
4. Packaging bag—you might wonder, does the packaging bag differ too? Yes. Some have hooded designs, and production costs vary widely. Different materials also lead to different prices. If silicone-coated fabric is used, the cost is 5–10 times higher than regular fabric, but it’s much smoother and easier to pack the sleeping bag.
5. Accessories—like Velcro and stitching thread. Though small, high-quality versions can cost 2–3 times more than cheap ones.
Overall, even though they’re both cotton sleeping bags, the average cost difference across all components can be 3–5 times. Hence, the price difference becomes apparent—and so does the quality difference.
Let me circle back to temperature ratings. Last month at the Asia Outdoor Show in Nanjing, a customer asked me about a new sleeping bag rated for -4°C. He was confused: “Why does XX brand’s -10°C bag sell for just 300 yuan, but yours, rated for -4°C, costs 600–700 yuan?” I happened to know the bag he mentioned, so I explained: “That XX cotton sleeping bag is filled with 300 grams of ordinary hollow cotton. Rating it for -10°C is their choice, but whether it actually works at -10°C is debatable. Our bag is filled with 400 grams of spiral hollow cotton, and our -4°C rating is a comfort rating, not a limit rating—and it’s rigorously tested and calculated.” The customer immediately understood but then asked: “Why does XX’s bag, with 300 grams of cotton, weigh 2.1 kg, while yours, with 400 grams, weighs only 1.8 kg? Doesn’t more cotton mean more weight?” “That’s the difference between a good sleeping bag and a cheap one. I use ultra-light fabric, which is over 6 times more expensive than XX’s, but it reduces weight while maintaining quality—so it costs more.”
The above is a real case, used here just to illustrate the point.
Most domestic brands prefer using limit ratings for their temperature labels, making the bags seem more valuable. In contrast, many European and American brands use comfort ratings, which I believe is more human-centered.
Cotton sleeping bags—a product that leaves consumers puzzled—are likely to remain so for a long time. I hope this article helps more people understand them better. (Source: Outdoor Information Network)