Rab Alpine Pro 400 Review

Keith, one of our gear testers has been putting the Rab Alpine Pro 400 Sleeping Bag through it's paces.

My old Taunton Leisure sleeping bag finally had to be ‘recycled’ – purchased in 1988, it had served its purpose dutifully, but the old hollowfill fibre had lost its insulating mojo. Up to date and the chance to test out the Rab Alpine Pro 400 – things were looking up!

I had used a Rab Andes 800 sleeping bag in a trip to Sweden and had been impressed by the insulating properties and functionality of the design, so with the Pro 400 I was expecting a similar experience. This updated unit from Rab is designed as a mid weight, warm and comfortable sleeping bag ideal for summer mountaineering / trekking when the temp can hit zero.

I was using it for the first time on a chilly late April weekend on Dartmoor.

The Features

Rab have made a really good bag, there is no doubt. Here is a list of the Pro 400’s features;

  • Trapezoidal baffle construction
  • Hydrophobic down (650 FB RDS duck down)
  • Angled foot box
  • Pertex Quantum water resistant shell
  • Zonal mummy shape
  • Chest and head baffles with adjuster toggles
  • ¾ length none snagging zip.
  • Limit -6 degrees– Comfort 1 degrees – Extreme -23 degrees!
  • illuminated zip tag – surprisingly useful.

In Use

Google the above features and you will get all the science and marketing, but in reality this bag is great. It was warm, and in my tent it was about 4 degrees, so getting a bit chilly. It was comfy – the ‘zonal’ mummy shape gave enough room to not feel hemmed in, but also reduced cold spots, which I liked very much. I had to admit to wondering how a slanted foot box would make much difference, but it does. Our feet naturally rest at an angle, so with the angled design no down is flattened out. My feet (usually cold) were kept warm – a first!

Rab have used the 650 fill power down in such a way as to reduce cold spots and keep as much of the warm trapped air close to your body – the trapezoidal construction! The small features, like a zip that works without getting snagged or the little internal pocket (great place to keep your phone) add to the good ergonomics.

In previous sleeping bags I always seemed to generate a lot of moisture/condensation and felt the sleeping bag was damp. It’s a common problem, but the hydrophobic down seems to reduce this noticeable along with the Pertex outer. Any slight dampness quickly evaporated once the sun was up.

In terms of carrying the bag about, it can be compressed to quite a small size and weighs in around 965 grams. This was pretty impressive regarding how warm it was for the amount of down used (400 grams).

I have now used the bag a few times in varying conditions and as yet no issues. It’s warmer than I expected for the size and weight and I haven’t been uncomfortable. I expect in sub zero conditions it will be fine if wearing thermal underwear, so it has plenty of scope for use across Spring through to end of Autumn.

Conclusions / thoughts?

So, are there any drawbacks? Well, it’s a down bag so needs a bit of care – but cleaning modern down bags is not a problem these days – use a liner to help with this. It retails at £265 which is a bit on money, though competitive with other brands, and you do get a bag that I am sure will last – you get what you pay for etc.

The sizing may be an issue (it suits a max height of 185 cm) if you are a bigger person – so best to try it out first.

If you were fussy, you might wish it came in both RH and LH zips – currently it’s only a Left Hander. I imagine this is a bit of streamlining in manufacturing. It didn’t bother me.

Overall, it’s a cracking bag for what it can do (weight, size, warmth) and I have now looked forward to camping out in less than warm but not freezing conditions. Next up it will be my bag of choice through the Alps this summer.


Two weeks in the Alps cycle touring - late July, tested the bag good and proper. 13 consecutive nights out, mostly camping at about 1000 + metres. I thought the bag might be too warm in the summer, but at night temps did drop close to 5 degrees on occasions. However, when it was a bit warm the ¾ length zip meant I could almost use the bag as blanket, which was great. The ‘glow in the dark’ zip tag was a surprisingly useful feature – the number of times I’ve tried to find a zip in the dark!

On one night I accidently spilled a whole bottle of water inside the bag – no issues, by the morning it had evaporated and the bag hardly felt damp and I was still warm. Seems hydrophobic technology works!