Sleep systems

UK Camp – Winter: System 2

Overbags are the big guns in Sleep Systems. PHD have a lot of experience with overbags, having made them for polar travel, high mountains and winter camping for years. As the name says, they fit over your main bag and greatly increase the warmth. In this system the Minim Overbag transforms the Minimus from +5°C performance all the way to -18°C.
Typical Operating Temperature
Guideline minimum temperature. Sleeping Bag TOT: you should get a night’s sleep, under normal circumstances. Clothing TOT: you should feel warm enough, assuming low/moderate activity. Sleep System TOT: relates to full system. For more details, see our Technical Briefing.
-18°C / -0.4°F
Schematic representation of Sleep System. Actual components differ.


  • System Products:
    • Main Sleeping Bag: Minimus (Sleep Rating: +5°C / 41°F) Weight 465g/16oz.
    • Plus Items:
      • Minim Overbag
  • Full System Sleep Rating:​ -18°C (-0.4°F)


If you intend to camp through the UK winter (particularly in Scotland), a Minim Overbag over the top of a Minimus is the simplest way to make sure you're going to sleep well. The combined bags will cope with temperatures down to -18°C. 

This System also offers the advantages that come with being based on two bags. The Minimus is a well-proven performer at +5°C, while the Overbag by itself gives a mid-way option at -5°C. That’s the whole year covered in the simplest possible way.

K SeriesThe Minimus K Sleeping Bag is available in the K Series: performance is the same, but the exceptional loft of 1000 down reduces the weight of the bag to an amazing 380g (13.4oz).

Review relates to Minimus Down Sleeping Bag

"Over the past twenty five years have tried and tested many bags but as yet I can honestly say, have not found a more comfortable bag."
Jeremy Hastings, Islay Bushcraft.

Review relates to Minim Overbag

"No one I know goes hiking in a big thick woolly jumper, so applying the layering principle to sleeping bags makes as much sense as it does for clothing. This past summer I used the PHD Minimus and PHD Minim Overbag sleeping bags.

Immediately the benefits became obvious. Two smaller bags took up about the same space as my old bag, but were considerably easier to pack into dry bags each morning. Stowing them in separate compartments reduced the chance of them both getting wet and made packing the kayak much easier with less wasted space.

On occasions when conditions were [warmer] the inner bag was more than sufficient on its own – at these times I didn't even unpack the second bag from the kayak, thus saving time and energy the following day. Being able to slide either the inner bag down round your legs or the outer bag off made regulating your temperature easy on warmer nights.

It's now so obvious - I can’t believe it's taken me 30 years to apply this layering principle to my sleeping system. "
Martin Rickard,

Sleep system components

Works well with
From £463.00 465g +5℃
Minimalist design cuts weight, but not warmth. For lightweight camping, mountain marathons, trekking, or as a backup.
From £577.00 780g -5℃
Used in combination with your lightweight Minim bag to boost its warmth by 23°C. A roomy stand-alone bag in its own right too.