Mammut Montana 2 review: GoOutdoors exclusivity 2 season sleeping bag

Mammut Montana 2 review

Synthetic sleeping bags like the Mammut Montana 2 are bulkier and heavier than their down counterparts. They do have the advantage of durability though and in 2 season bags the size and weight can be kept to a reasonable level. We’ve had the chance to test this GoOutdoors exclusivity during May and June 2013, with some great camping time. Here is what we thought of the Montana 2.

Insulation, comfort

Mammut Montana 2

The OTI™ Element (100% polyester) insulation from Mammut does not have much loft, which is fine for a ‘Spring’ sleeping bag. The box construction of the bag is good and keeps the insulation evenly spread. After various nights and trips in the washing machine the OTI Element was still well distributed and no cold spots where felt. The 450g of filling gives this bag a rating of 24°C to 8°C for comfort, 8 to 4°C transition and 4 to -11°C risk. This last range is of course assuming you are wearing warm cloth at night and is not recommended at all.

We are well into summer here in Spain but nights can be cool, specially this June when I did most of the testing. The Montana 2 was tested in temperature between 18°C and 12°C, in low humidity. Sleeping in underwear, it did not get too cold nor too warm and always experienced a good night sleep. I think 24°C would be pushing it, especially since the zip is not full length and will not let you put your feet outside.


The inner is made of SoftTX fabric. Although synthetic generally means more sweat this was not a problem here. It is smooth but not slippery like some cheap synthetic fabrics can be. Somewhat comparable to micro-fleece.

Mammut Montana 2 top

The Mammut Montana 2 is a mummy shaped sleeping bag and as such is narrower at the legs. A very roomy foot box however makes it as comfortable as a bag of this type can be. The hood is OK and it also comes with a draft collar, a bit on the small side however.

Weight and size

Advertised as a lightweight 2 season bag we can report that it is indeed lightweight. 903g without the stuff sack, 985g in total. The said stuff sack is big and allows you to shove the Montana 2 without any trouble. The compression straps will bring the size down to around 220x220x240mm. I’d recommend to not leave it compressed like that for storage. Give the bag all the space of the compression bag will increase it’s lifetime. Insulation does not like to be compressed for long periods of time, synthetic or down.

Packed next to inflatable pillow


Mammut inflatable pillowAlthough there are better options for weight or temperature it is hard to beat the Mammut Montana 2 on price. Exclusive to GoOutdoors stores, it can be had for £60 with the members card or £80 without. This is surprisingly great value from a big brand like Mammut. The simple but effective construction and the resilient Balance outer fabric should hopefully ensure this bag years of good service.


A few nice details, a decent weight and size, comfortable sleeping and very good value. If you are in the market for a resistant sleeping bag for summer adventures, traveling and even festivals, this is an easy recommendation.

[note]The Mammut Montana 2 was given to us for the purpose of this review. We try our best to not let this affect our views in any ways. Our gear tests are done in real life, during our own outdoor activities.[/note]

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