TheraPur ActiGel Alaska 6000 Combination Super King 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
£2,399
Get the lowest price we've found
Save with the previous model
Some retailers still sell the earlier version of this mattress for less than the current model's best price.
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
- Distance from a fidgety partner: With 90cm each for two people sharing, a partner who turns over all night is simply further away, which often helps more than a softer comfort layer would.
- Space when a child wanders in: When a little one climbs in during the small hours, the 6ft width lets two adults and a small child settle without anyone clinging to the edge.
- A share left over for the dog: If a large dog sleeps on the bed as a matter of routine, the extra width stops it quietly taking over your half.
- Cooling cover across the full width: The graphite-infused ActiCool+ cover spans all 180cm, so with more bodies in the bed, the whole surface is designed to help with heat and moisture.
- In proportion with a big bedroom: In a period property or a generous master bedroom, a UK super king fills the space properly, where a UK king can look slightly lost.
This size suits you if...
You share with a partner who tosses and turns, or a child or large dog regularly joins you, and your bedroom comfortably clears our suggested minimum of 3m x 2.9m.
Consider another size if...
Your room falls short of 3m x 2.9m, or two of you sleep without much disturbance. We'd recommend the UK king instead, which needs at least 2.7m x 2.9m.
Similar Mattresses in This Price Range
Did you know? On Mattress Unboxed we have over 1,000 different mattresses to suit all types of sleepers. View all mattresses.
FAQ's
Is a TheraPur ActiGel Alaska 6000 super king big enough for two adults and a child?
For occasional visits, yes. Two adults get 90cm each in a UK super king, so a small child can tuck in without anyone hanging off the edge. Bear in mind the mattress is rated medium soft, so if everyone gathers towards the middle, expect a fair amount of give.
What size room do I need for a super king TheraPur ActiGel Alaska 6000?
We suggest at least 3m x 2.9m for a UK super king. In a loft conversion, check where the ceiling slopes first, because the headboard wall needs full height across the whole 180cm. Leave clearance for the door to swing past the bed, too.
TheraPur ActiGel Alaska 6000 king vs super king: is the extra width worth it?
The UK super king is 30cm wider than the UK king and the same length, giving 15cm more each for two sharing. If a restless partner or a regular small visitor is the problem, that space matters. If neither applies, the UK king needs less floor: we suggest at least 2.7m x 2.9m.
Will a super king Alaska 6000 fit up my stairs and round the landing?
A UK super king measures 6ft x 6ft 6in, so the trouble spots are usually tight landing turns and narrow doorways rather than the bedroom itself. Measure the stairs, the landing and the bedroom door before you order, then compare the retailers listed on this page.
What bedding fits a TheraPur ActiGel Alaska 6000 super king?
You'll need super king fitted sheets and a 260 x 220cm duvet, so king sets you already own won't carry over. TheraPur doesn't publish a depth for this mattress, so if you're buying sheets in advance, deep-pocket ones are the safer choice.