TheraPur ActiGel Alaska 6000 Combination King Size Mattress
The TheraPur ActiGel Alaska 6000 Combination Mattress pairs a graphite-infused ActiCool+ cover with a 6cm layer of zoned ActiGel foam, which means a medium-soft feel that manages heat and supports where you need it.
- Graphite cover keeps you cooler
- Zoned foam support where needed
- Medium-soft feel for side sleepers
£2,239
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TheraPur ActiGel Alaska 6000 Combination Mattress
More available sizes
Mattress details
Mattress
TheraPur ActiGel Alaska 6000 Combination Mattress
Size
Firmness
Medium Soft
Construction
Foam
Gel
Depth (cm)
Layers
2
Layer Details
ActiCool+ cover
A graphite-infused cover at the very top of the mattress, designed for heat control and moisture wicking. It's the first thing you lie on, so it helps you stay cooler. The cover is also free from chemicals.
ActiGel zoned foam layer
A 6cm layer of zoned ActiGel foam, TheraPur's deepest, which supports the areas of your body that work hardest. TheraPur says ActiGel transfers heat faster than standard memory foam, so it should feel less warm too.
Layer details from dreams.co.uk product page, November 2026.
Key benefits
- A little more room each: At 75cm per person, you get 7.5cm more personal space than on a UK double, which means slightly less elbow contact when either of you rolls over.
- Length for taller partners: The UK king is 200cm long, 10cm longer than a UK double, so a partner over six foot can stretch out fully without feet pressing past the end.
- Space from an early riser: If one of you gets up hours before the other, the extra width puts a bit more distance between the sleeper and the person climbing out in the dark.
- Cooler with two sharing: Two people under one duvet build up warmth, and the graphite-infused ActiCool+ cover is designed to draw heat and moisture away from the surface.
- Fits a typical main bedroom: We suggest a room of at least 2.7m x 2.9m, which is less floor space than the 3m x 2.9m we'd suggest for the UK super king.
This size suits you if...
You share the bed every night and the UK double has started to feel cramped, one of you is close to or over six foot, or you like a medium soft feel but want more distance from a partner who keeps different hours.
Consider another size if...
Your bedroom is smaller than our suggested 2.7m x 2.9m. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
How much space does each person get on a TheraPur ActiGel Alaska 6000 UK king?
Two people sharing get 75cm each. On the UK double you would have 67.5cm each, so the UK king gives you 7.5cm more per person. It sounds modest on paper, but it's the difference between brushing shoulders all night and having a small gap between you.
Is the UK king TheraPur ActiGel Alaska 6000 long enough for someone over 6ft?
At 200cm, or 6ft 6in, the UK king is 10cm longer than the UK single, UK small double and UK double. For a partner over six foot, that extra length is often the real reason to size up, since it gives room to stretch without feet hanging off.
What size bedroom do I need for a UK king TheraPur ActiGel Alaska 6000?
We suggest at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable. In a new build master bedroom, measure after the wardrobes go in, because fitted furniture can take more floor than you expect and leave little room to walk round the bed.
Should we choose the UK king or UK super king TheraPur ActiGel Alaska 6000?
The UK super king gives 90cm each, so the UK king gives you 15cm less per person. Both are 200cm long. The UK super king needs a room of at least 3m x 2.9m, so if your bedroom is tighter than that, the UK king is the sensible upgrade from a double.
What bedding fits a king size TheraPur ActiGel Alaska 6000?
Standard UK king sheets fit the 150 x 200cm surface, and a 230 x 220cm king duvet suits it. TheraPur doesn't publish a depth for this mattress, so check the pocket depth of fitted sheets against the mattress itself once it arrives.