New for 2019, the Tanager is a simple, ultralight product from Feathered Friends that is essentially an ultralight makeover of their Vireo model. It is designed to have as few features as possible in order to keep weight low and maximize efficiency and warmth. U ultralight backpackers and mountaineers – people who value low weight above any other feature – represent the target audience.

Featuring a non-traditional design, the Tanager has no hood and no zipper. It is essentially just a tube sack stuffed with high quality down.

Weight

The Tanager wins our weight metric. It is the lightest product in this 3-season review. Our verified weight – the lightest of all models tested – is 1 pound 3.8 ounces. But this is deceiving because we tested a size long, not a regular length, and we tested a final prototype, which has a heavier lining material than the final product. As a result, we believe Feathered Friends when they say that the weight of a typical regular length model is only 1 lb, 2.6 oz. That low weight blows the rest of the bag weights out of the water.

This remarkable weight is achieved in a couple of ways. First, there is no hood and no zipper, which greatly reduces the weight and bulk. Second, the materials used are the latest in lightweight textile technology. The shell is Pertex Quantum 7-denier fabric with DWR and the lining is Flite 15-denier ripstop nylon. Both of these materials weigh as little as possible while still remaining functional.

Compressibility

The Tanager features with 950+fill goose down. This is about as high-quality as you can get. It not only insulates well, but it compresses extremely well. This bag can be pressed into a tiny package that barely takes any space in a backpack. Without a hood and a bulky zipper, this bag gets even smaller than bags of a similar size and weight. In order to maximize the compressibility of this bag, we suggest purchasing an after-market compression sack because it does not come with one. It can pack far smaller than the included stuff sack allows.

Warmth

With no zipper and a full box-baffle construction, this bag has no cold spots. It doesn’t have a way to ventilate, but it also does not let cold air in either. It is like wearing a cushy, warm cocoon. The drawcord around the collar allows the sleeper to pull the bag tight around the shoulders and trap warm air inside. The main downside in terms of warmth is that this bag lacks a hood. In most cases wearing a beanie, a Buff around the ears, or a fleece with a hood (something like a Patagonia R1) will be all that is needed to feel comfortable in this hoodless bag. If the temperatures are really cold, pair it with a down hooded jacket and you won’t even notice that you aren’t in a standard sleeping bag.

One tester took the Tanager with him on a three-day ascent El Cap. Big wall climbing involves heavy gear and a haul bag full of water, so he hoped to offset some of the weight by using this lightweight bag. On nights on the porta-ledge, there were thousands of feet of air underneath him while he slept. He did use a sleeping mat, but the potential for cold nights was high. He was comfortable and happy inside the Tanager, which is a testament to the warmth and functionality of this bag.

Ventilation

Since the Tanager is just one continuous tube with no zipper, there are no ventilation features whatsoever. The one saving grace in this respect is that there is no hood to trap stuffy air inside. If fresh air is needed, the whole top of the sack can be pushed down. If ventilation is a must-have feature, we suggest one of the quilt-like options such as the ZPacks Classic Sleeping Bag or the Therm-a-Rest Vesper. Both of these bags weigh only a tad bit more than the Tanager and provide more versatility for warmer weather.

Features

The primary feature of the Tanager is its simplicity. The only actual feature on this pared-down sack is a drawcord cinch around the collar. This secures the bag closed and keeps warm air inside. In colder temperatures, this bag is intended to be used with a lightweight hooded down jacket. For ultralight hikers and mountaineers, this makes sense: you would already be carrying this additional item anyways, so why duplicate the weight of an insulated hood on your sleeping bag? This economical design is ideal for those dedicated to lightweight travel in the backcountry but is probably not seen as comfortable for those who aren’t planning on long distance hiking and only occasionally spend nights in the backcountry.

Durability

Using a 7-denier shell material is a risky proposition for a sleeping bag. Especially a down-filled one. The lowest denier on any of the other bags in this test was 10d. However, this Pertex Quantum textile seems to hold its own. After several backcountry climbing trips and hauling this bag up El Cap and sleeping with it on a porta-ledge, it has held up just fine. We haven’t seen a single hole or tear. The lack of a zipper actually increases the durability of this product, because that is one less thing that could malfunction. Because of the high quality down, we think if this bag is cared for properly it could last years.