Multimat Expedition Summit 38S Compact Self-Inflating Mat

Multimat's Expedition Summit 38S - "A Cold Weather Masterpiece"

Scramble's summary of the Summit 38S does a better job than we could at summing up the features that make this mat a real gem for anyone wanting a comfortable sleep in deep sub-zero temperatures. We strongly recommend a read of Scramble's review, especially to see why a reliable and durable, compact, two-thirds length sleeping mat is the way to go for those trying to reduce their winter pack weight without sacrificing comfort.

The Summit 38S is supremely comfortable and offers a high degree of insulation from the freezing ground. Non-slip silicone and PU coatings provide a water-resistant top-surface and a genuinely waterproof base while ensuring the mat isn't sliding around inside your tent or slipping out from under you like a bar of soap. Unlike air-pads, the self-inflating Summit has a flat upper surface, ensuring its full stated width is available to the sleeper. A stand-out feature is the excellent (removable) valve that provides a reliably secure seal and makes inflation hassle free.

The Summit 38S combines relatively light-weight durability, luxurious comfort and outstanding cold-weather performance at the kind of price that should scare (or should have scared) the Expeds and Cascade Designs of this world.  Practically faultless in both design and performance, the Multimat Expedition Summit Compact 38S is Scramble's top pick in the Cold Weather (Sub Zero) Sleeping Mat category.

Compact Self-Inflating Mats: The Ideal Compromise

There are basically three types of sleeping mat:

1. Closed-Cell Foam Mats
2. Inflatable Air Mattresses (Air Pads)
3. Self-Inflating Mats

In simple terms, so-called "self-inflating" mats are a cross between (1) and (2). This means you get some of the foam-based insulation from (1) and some of the comfort (and arguably a better sleep) from (2). Self-inflating mats pack down much smaller than closed-cell foam mats, and require much less air to blow up than air mattresses.  There are other downsides to air pads, rarely discussed: durability, reduced insulation via convection caused by "air-pumping" as the user moves in their sleep, steep rolled edges meaning less usable width etc ...

The bony areas of the body that really appreciate some cushioning are the hips, shoulders and back. So, to keep the weight to a minimum, a short-length (2/3) mat combined with your pack (under your lower-leg and feet) is really all that's required.

A Brief Note on Long Term Storage

Just as sleeping bags should not be stored compressed in their stuff sacks, the same goes for self-inflating mats. If stored packed, the foam will get overly compressed and won't be able to full expand when inflated. When you inflate the mat, moisture from your breath gathers inside the foam. This is not a big deal during a trek, but can be when stored for long periods. When storing, inflate the mat fully but keep the valve open; some air will escape but the foam won't be compressed. If stored vertically, make sure the valve is at the top. With the valve open any residual moisture will evaporate and won't negatively impact the foam.

Features:

• Type: Compact (2/3 Length) Self-inflating
• Season Rating: 5  (~ -15°C to -20°C, see Scramble's review)
• Range: Expedition
  
  
• Antibacterial ether TPU membrane formulated for lower temperatures
• Quality lightweight vertically & horizontally drilled high insulation/rebound 16kg/m3 PU foam core for lasting performance
• Unique 'warm zone' in torso area for improved tog value
• Large removable valve for fast inflation/deflation and servicing
• Microfibre-lined stuff sack/pillowcase retaining band & repair kit
• Water-repellant coating on upper face fabric
• Waterproof coating on the base fabric
• Component temperature tolerance: -35°C to +50°C
• 12 month manufacturer guarantee

* Note on (estimated) RRP

The Summit Compact 38S is no longer made by Multimat and so to get a relevant current RRP for this model, we've looked through the Multimat range and checked the percentage price difference between their compact (S) models and their regular full length models. We've then applied this reduction (which is consistently ~80%) to the current RRP for the Expedition Summit 38 full length model (£90). The resulting RRP (for 2020) comes to £72.00. Which makes sense in light of their NATO model (£65 RRP) which though insanely durable, is substantially heavier and provides significantly less insulation.

Full Specification: