ALPS OutdoorZ Redwood -10 review: the warmest car-camping bag we found

The ALPS OutdoorZ Redwood -10 is our cold-weather car-camping pick in the best sleeping bags for camping guide. This research review covers the published specifications, the temperature-rating caveat, and where its size and construction make sense.

Who it is for

This bag fits one buyer especially well: someone who sleeps near the car and values a roomy, heavy sleep system. The two-layer offset TechLoft synthetic fill, cotton flannel liner, and 38-inch width prioritize insulation and space over packed size.

It is unsuitable if you carry your gear on your back. The Redwood weighs 11 lb 8 oz and rolls up full-width rather than compressing into a small stuff sack, so it is a trunk-and-cabin bag. Use the sleeping bag warmth calculator as a planning aid, then leave additional margin because this model's rating is not a published ISO comfort result.

Full specifications

The single spec people get wrong: this is a synthetic bag, not a down bag, despite the cold-weather rating. The warmth comes from a generous two-layer offset TechLoft fill and the heavy cotton construction, which is exactly why it is so warm and so heavy at the same time.

Pros and cons

What it does well:

• Heavy insulation, a draft collar, and offset construction designed for cold-weather car camping.
• Soft cotton flannel interior with a roomy rectangular cut.
• Oversized 38-inch width that suits restless and side sleepers who feel boxed in by mummy bags.
• Durable canvas and flannel build with offset stitching that keeps the insulation from shifting, backed by a lifetime warranty.

Where it falls short:

• Large packed size, since it rolls full-width rather than stuffing into a sack, which makes it unsuitable for backpacking.
• Heavy at 11 lb 8 oz, so it lives in the trunk and the cabin, not the pack.
• Cotton absorbs moisture quickly and dries slowly, so keep it dry and air it out after damp trips.

How it compares

Against the Kelty Cosmic Down 20, the trade is heavy rectangular construction versus weight and packability. The Cosmic Down 20 uses down fill, packs smaller, and has a published ISO comfort result. The Redwood offers more interior space and a flannel liner but lacks an equivalent standardized comfort figure.

Against the budget Coleman Brazos, the Redwood uses heavier materials, a wider cut, and substantially more total weight. Neither model publishes an ISO comfort result, so compare their construction and intended use rather than treating either product name as a laboratory guarantee.

For the full field, including lighter three-season options and budget picks scored the same way, our best sleeping bags for camping guide goes deeper, and the Redwood is our top overall pick there. To match any of these bags to the actual lows you expect to camp in, the sleeping bag warmth calculator is the fastest way to avoid buying too much or too little bag.

Frequently asked questions

Is the ALPS OutdoorZ Redwood -10 actually warm to -10F?

ALPS rates the Redwood to -10F, but we could not verify a published ISO 23537 comfort result for this model. Do not interpret -10F as the temperature at which every sleeper will be comfortable. Leave margin for your pad, shelter, clothing, wind, moisture, and personal sleep temperature, and test the full system in controlled conditions before remote cold-weather use.

Is the ALPS Redwood good for backpacking?

No. At 11 lb 8 oz and with a full-width roll rather than a compression stuff sack, the Redwood is a car-camping, hunting, and cabin bag. If you need to carry your bag on your back, look at a lighter down option like the Kelty Cosmic Down 20 instead.

Is the Redwood down or synthetic insulation?

It is synthetic, using a two-layer offset TechLoft fill rather than down. Synthetic insulation handles damp conditions better than down and keeps the cost down, though it is part of why this bag is heavier than a comparable down bag.

How big is the ALPS Redwood inside?

The bag opens to 80 by 38 inches, so the 38-inch width gives noticeably more room than a standard mummy bag. Restless sleepers and side sleepers tend to appreciate the extra space, and the rectangular shape lets two compatible bags zip together.

ALPS Redwood vs Kelty Cosmic Down 20: which should I buy?

Choose the Redwood if warmth and a plush, bed-like feel matter most and you camp near the car in cold weather. Choose the Kelty Cosmic Down 20 if you want a lighter, packable down bag that works for backpacking and milder three-season trips. The Redwood is warmer and cozier; the Kelty is lighter and more portable.

For the full field, including budget and three-season alternatives scored the same way, see our best sleeping bags for camping guide.