Rab Neutrino 400 - Women's Review

This lightweight, minimalist bag is packed with 800 fill power ethically harvested Nikwax Hydrophobic down. It packs down small, is lightweight, and keeps you warm in summer conditions. The Neutrino is an ideal summer bag for a frequent backpacker or alpine climber.

Performance Comparison

Warmth

The Neutrino is a warm sleeping bag, but not the warmest of the bunch. Rab notes that it has an EN rated at 30°F for comfort, with a limit of 27°F; we find the EN limit rating of 30°F to be right on the money. We tested this bag in Yosemite Valley on some cold shoulder-season nights, where temperatures fell below freezing some mornings, and we felt warm in this bag inside a tent, on a warm sleeping pad. Its redesigned chevron-shaped baffles are meant to keep down in place over your body and eliminate cold spots more effectively. We can't say we noticed a difference with this change.

Rab makes their women's sleeping bags 5 to 7 inches shorter in length and slightly slimmer than their men's sleeping bags, but they use the same amount of down fill for both. This means that the women's bag has more down per square inch and is warmer than the men's version. The cozy neck baffle and draft tube along the zipper kept out the cold air well. Pair it with a lightweight air mattress and you'll have a great lightweight, compact, 3-season backpacking sleeping kit. The Neutrino only has 14 ounces of 800 down fill, but it should be said that it is just as warm as the other down sleeping bags we tested with lower quality 650 fill.

Weight

Weight is the category where the Neutrino excels. Rab has made a great effort to minimize the weight of this sleeping bag by paring down its features and materials, but still retains the necessities.

Weighing only 28 ounces, or 1.75 pounds, it is a pleasure to pack this sleeping bag in your backpack. By using high-quality down, the bag can be very toasty without being bulky or heavy. We think that Rab could have used a ¾-length zipper as they have on past Neutrino models to cut down the weight of this bag even more. The shell material is very lightweight, which is great for weight savings, but is consequently quite delicate and seems more prone to molt down, which is a drawback.

Comfort

The Neutrino is very comfortable. It is on the roomy side for a mummy bag, and we never felt constricted. Its shell and liner fabrics feel light and soft against the skin as well. The bag even has an ergonomically shaped foot box so there is space for your feet as well as any wet socks or boot liners you may want to stuff in there to dry overnight.

Packed Size

Once again, the high-quality down is to this bag's benefit, because it compresses to a small size. Rab has changed the Neutrino's stuff sack this iteration. It is a much larger roll-top design that may be water-resistant but it is less easy to compress the bag down in this large sack. This bag could potentially be compressed more with a traditional compression sack if you need to create even more space in your pack. It also comes with a cotton storage sack so you can store it away uncompressed to help keep its loft.

Features

At first glance, this bag does not appear to have many distinct features. It is just a big blue tube. But look closer, and you will discover that many features are hidden just below the surface — literally. The main feature that Rab has introduced for its Neutrino line is Nikwax Hydrophobic down. This down treatment has been specially formulated between Rab and Nikwax in an attempt to make the down absorb less water, dry faster, and retain its loft longer. This treatment does not make the bag waterproof, nor does it take the place of synthetic insulation in wet conditions, but rather allows the bag to function at a higher level for a longer period when the weather is not ideal. Most down sleeping bags we tested now come with some hydrophobic down.

The Neutrino also has more visible features like the small stow pocket for you to stash your headlamp or contact case on cold nights. We found the drawcords around the face and neck awkward to use and wish they used two separate diameter cords, they have slightly improved in the newest iteration of this product, but they're still not great.

Value

This is one of the more expensive bags in the review, not quite as much as those right at the top of our scoring. Our testers love this bag and think it has a lot of great features to compete with some of the lighter sleeping bags on the market. However, this is no longer the only competitor in the lightweight women's category and is no longer a great value. We think there are a few bags that are less expensive, but just as great.

Conclusion