MSR Twin Sisters

The Twin Sisters is an excellent lightweight and minimalist mountaineering shelter. It offers a lot of space for its weight, and it's very easy to pitch.

The Twin Sisters comes standard with collapsible, shock-corded aluminum poles and a set of six stakes. The included stakes are fairly standard MSR stakes, good for pitching in soil, but not in snow.

The fabric is a 30 denier ripstop nylon with the MSR proprietary Durashield coating. It's a bit on the heavy side compared to good silnylon, but it's also durable and waterproof. The shelter comes with guylines already attached to the tie out points.

The pitching procedure is very simple. Stake out the 4 corners pulling the edges tight, then open one end an insert the poles into each peak. Then stake out the side tie outs and pull the corners tight as necessary. The entire process takes just a minute or two in regular soil. In snow, allow some time to pack the snow down and bury the anchors to make sure that they hold.

If you are using the included straight poles, all you have to do is assemble them. When I pitch the Twin Sisters with trekking poles, I set them a bit on the short side and lengthen them to make the shelter taut.

For use in snow, you will need different anchors. I use MSR Blizzard snow stakes.

The snow skirt is quite nice for sealing out drafts, and also helps to stabilize the shelter against wind.

The shelter has vents at each peak, with loops that you can tie out for extra stability if necessary. The peaks also have tie out loops on them to allow for exterior pitching. This way you can keep the poles out of the middle of the shelter.

It's pretty solid as is, but you can add stability with the simple expedient of putting rocks or snow on the snow skirt. The skirt is made from a more robust fabric than the rest of the shelter, so durability shouldn't be a problem.

When pitched, it has an elongated hexagonal shape. There is plenty of room on either side of the poles for a mattress and sleeping  bag or quilt, so fitting two people inside is easy enough. Each end has an entrance and a generous vestibule. Each entrance opens up the middle, and both side flaps on each entrance have tieout loops. With this, it's possible to pitch the shelter as an open-ended a-frame, or open one side of the vestibule, or some combination thereof.

The fabric is heavier than silnylon, but should hold up well under use, and MSR has a well-earned reputation for standing behind its products.

The snow skirt is a double edged sword. It's nice for keeping out drafts, but it's also extra weight when you don't need it. In winter and mountaineering it's still lighter than a standard 4-season tent, but modern 3-season tents are only slightly heavier. In addition, there isn't any built-in mechanism for securing the snow skirt, so unless you're willing to modify the tent, they'd work against you in mild climes when you would want some additional ventilation to keep cool. Even then, they'd still be extra weight for no benefit when compared to a standard flat tarp.

When I used this shelter in snow with temperatures that dropped below 10 degrees Farenheit, I buried the snow stakes and used a small candle lantern inside while I was awake. It did help to warm the tent, and I didn't feel any drafts. There was frost on the interior of the tent in the morning, since I was a bit overzealous about sealing off the bottom of the tent. I placed my pad on top of a thin foam pad to keep it out of the snow.

That said, it's a mountaineering shelter, not a fair-weather shelter. If you're willing to carry a few extra stakes or jury rig them with found materials, it would work fine in milder conditions but wouldn't compare favorably with other 3-season ultralight shelters.

Here is a short video showing a basic pitch.

Purchased this tent on clearance at REI. Its regular MSRP is $299. While it's a bit on the heavy side for an ultralight shelter, I recommend it as an extreme conditions shelter.