Borah Gear Cuben Bivy

Hiked It. Liked It.

The Borah Gear Cuben Bivy is a lightweight bivy sack that’s available in several lengths/width combinations. Mine is a long-wide with Cuben Fiber (bottom) and M90 (top) with a full mesh face panel and side zipper. This is custom material combo, as Argon is what Borah Gear normally uses for the top of their Cuben Bivy’s. I’ve owned this bivy since 2013 and have been very happy with it. Here’s the scoop…


All specs as claimed unless noted otherwise…

  • 78″ girth x 88″ long (allowing for a couple inches of bathtub at each end)
  • #3 YKK zipper extending partially down one side
  • Packed size of ~ 3 x 9 inches
  • Total weight 5.3 ounces in .74oz Cuben and Momentum 90 (Long-Wide size and includes Cuben stuff sack)
  • MSRP: $180
Packed Size
Packed Size


The Borah Gear Cuben bivy is one of several similar bivy sacks that they offer. The Cuben is basically one material combination (Cuben/Argon) whereas the other bivvies have several material choices, however John West was able to easily accommodate my request for an M90 top. This one is a side zipper, so the zipper extends across the chest and then down about 24 inches of the side.

Borah Bivy combined with a Tarp
Borah Bivy combined with a Tarp

I’ve been on everything from snow to sand with my Borah bivy and it’s been great. This isn’t a “storm bivy”… you wouldn’t lay out in a the rain or snow up against a rock hoping to stay dry, but it does offer a nice measure of protection from the elements when either used alone, or with a shelter. The Cuben bottom offers good protection against wet ground and should be used in combination with at least a light groundsheet to minimize the chance of punctures and abrasion. The M90 top provides some water resistance and offers protection against rain splatter, dew, and windblown snow. It’s also a very breathable material and I’ve had very few issues with condensation. When the conditions dictate that condensation will be inevitable I’ve found the amount which does form inside the bivy has been manageable (I never breath down into my bivy)… of course this can vary, but all things being equal I’ve been happy with the M90 and believe it to be a great choice in most conditions and when supplementing the bivy with a light shelter in bad weather.

The long sizing is necessary for me since I’m just over 6′-3. I believe John made my bivy just slightly longer usual since I mentioned to him that I planned to use it in the winter and would have a lot of insulation inside which I didn’t want compressed. For that reason I also elected for the wide sizing option. This gives me just enough room to fit a down air mattress, a 20º sleeping bag, and a 30-40º quilt over the top of that, for a setup that can extend to 0ºF and beyond. I’ve actually gotten to the point that I really like using the bivy even in fair weather when I’m taking a quilt. It’s like getting a warm hug from a friend! The quilt stays in place, drafts are eliminated, it adds a tiny bit of warmth, gives extra protection against the elements, and keeps the bugs out when I have it zipped up… because of the long-wide sizing, I don’t don’t get the claustrophobic vibe.

Somewhere in the Wild Grasslands of Marin
Somewhere in the Wild Grasslands of Marin


  • Construction is nicely executed
  • Momentum 90 is a great light and breathable top material while still offering some water resistance
  • Ease of ordering and lack of up-charges for every little option

Not So Much…

  • I wouldn’t really call it a dislike, but if the zipper extended just a little further down the side that would be nice.

Famous Last Words

The Borah Cuben Side Zipper is well designed and built, very light, and reasonably priced. Borah Gear has built their growing business on the platform of their bivy sales which might tell you something about the merits of these bivies. Hike It. Like It.

Jacob D Written by:

Jacob is the head honcho, wearer of many hats, and modern day berserker here at Hike It. Like It. When he's not out hiking or running the trails you'll find him operating in full capacity as a Super Dad and chipping away at a degree in Kinesiology. This guy likes to stay busy. Follow on Strava


  1. Owen
    March 3, 2017

    Hi, I know this is an old post, but I thought I would ask anyways. I’m trying to decide between a few bivys including the Borah one. My problem with sleeping in a bivy in the past has been dealing with the feeling of bug netting on my face, even as a side sleeper. In your first picture with it under the tarp, it looks like you have great clearance! Does it feel that way? Is it zipped up in that picture? I noticed the hang loop is offset from the zipper, unlike the MLD and Katabatic bivys–does that you have bug netting hanging on your face if you don’t have it zipped up? (if that makes sense)


    • March 4, 2017

      Hi Owen. To be honest, I always zip it up and use the loop wit shock cord to keep it off my face. With it unzipped it might dangle on your face (I can’t confirm right now). A second loop near the zipper might be something Borah could add for you.

  2. JR
    September 27, 2016

    Hi, would you mind giving a rundown on why you chose M90 over Argon for the top?

    • September 27, 2016

      Hi JR. Good question. It’s been a while, but if I recall correctly M90 is a little more water resistant than Argon (and is probably a little less breathable as a result). Both materials are very light, both are highly breathable, and neither will keep you dry in a storm, so it all comes down to personal preference at the end of the day. I don’t think there is much “real world” difference. I have been very happy with the M90. On a recent trip I let a friend borrow my bivy to use under his Hexamid Solo… he stayed totally dry while I ended up with some condensation while sleeping in my Echo I (!)

  3. bcyork
    July 21, 2015

    Really let down by John @ Borah Gear. I had ordered a tarp on 6/24/2015 and asked if he could have it shipped by 7/22/2015 and he said he would. On 7/21/2015 I get an email telling me he was canceling my order. Claimed there was only about 10 people that he was having to cancel on because he wasn’t for sure when he would get them finished as the person sewing them quit (not sure why he didn’t fulfill them with only 10) but I had waited more than the typical three week lead time. More than that he waited till the day before I needed it to ship to get it on time for a trip and canceled. I responded right away as soon as he emailed me and decided not to respond after 6 hours. I now have a week till a big trip and John really screwed it up by misleading me and just being a poor business owner. Also as far as customer service his normal time for responding to emails is 3-5 days and clearly he forgot about my 7/22 shipment date he agreed to as his seamstress was finishing the last few in the queue before leaving and mine wasn’t apparently in there despite needing it done the next day. Undependable business owner.

    • July 22, 2015

      Ahh man… Sorry to hear about your experience. Stability or lack of stability can be problematic with the cottage businesses, especially the smaller ones. As a general rule I would advise against ever making a key purchase from a cottage manufacturer with a super tight time window like that. I’m not saying this was your fault in any way, because from what you wrote it doesn’t sound that way, but just a caution because unfortunately stories like yours are not uncommon among the smaller businesses in general.

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