4S Inner

On its own this is only suitable for Bothies or camping between May and August.

Combined with the 4S Outer, this can be used all year round in sheltered places.

With the further addition of the Thermaliner, either between the Outer and Inner or inside the Inner as protection against dirt, you have a full 4+ Season system, for comfort all year round.

  • AquaTherm Extreme pile lining
Available colours
  • Black
  • Olive Green
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  • Three quarter length non-locking front zip.
  • Hooded.
  • Tape loops for attaching to Outer or Thermaliner.
  • Easy to wash (although a launderette is recommended).
  • Supplied in stuff sack.

Sizes: S / M / L / XL

Weight: 1180g

4S Inner Small Medium Large X Large
Suitable for height up to 5’6″ 5’10” 6’3″ 6’7″
Suitable for weight up to 112 lbs
50.8 kg
168 lbs
76.2 kg
210 lbs
95.3 kg
238 lbs
107.9 kg
Pack Weight (approx) 1110 1200 1360 1440
Pack Size (approx) 31×23 34×23 40×23 46×23



All measurements are approximate. Buffalo Systems Limited reserve the right to amend any specifications in the interests of improving our products.


1 Review

  1. Tony says:

    I have owned the 4S Inner for the last 15+ years and have used it extensively in conjunction with an MOD issue sleeping bag. Trust me, it makes all the difference to that 4am experience when you start to feel the cold under you and it becomes difficult to drift back off – this has never been an issue with the 4S Inner. I also use it quite often on its own indoors where it is perfect for just rolling out when needed. Virtually indestructible, it has worn the years well! I just need to find someone that sells the Thermaliner now so I can use it outdoors on its own in warmer weather!

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