Coolflex Lux Ortho Pocket King Size Mattress
The Coolflex Lux Ortho Pocket is an extra firm hybrid mattress, which means it pairs pocket springs with foam for a supportive, no-sink feel.
- Genuinely firm feel
- Minimises partner disturbance
- Pressure relief without deep sink
£319
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Coolflex Lux Ortho Pocket Mattress
More available sizes
Mattress details
Mattress
Coolflex Lux Ortho Pocket Mattress
Size
Firmness
Extra Firm
Construction
Foam
Pocket Spring
Hybrid
Rolled
Orthopaedic
Depth (cm)
24
Layers
3
Layer Details
Knitted Cover
A soft knitted cover that breathes well, which means heat can escape rather than build up around you. It helps keep you at an even temperature all night.
Reflex Foam
A soft layer of Reflex Foam that contours to the shape of your body, which means personalised support and pressure relief where you need it. It gives a comfortable surface without undermining the firm feel beneath.
Pocket Springs
Individual pocket springs work independently, reacting to changes in your weight and movement. In practice that means responsive support at your pressure points and less motion transfer across the bed.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Room to sleep apart, together: At 75cm each for two people sharing, you can both find your position without negotiating territory in the middle of the night.
- Springs that keep the peace: The pocket springs react independently to weight and movement, which means a partner leaving hours before you is far less likely to wake you.
- Length for taller sleepers: The UK king is 10cm longer than the UK Double, a real difference for anyone whose feet reach the end of a standard bed.
- A firm surface across the full width: Extra firm support with Reflex Foam contouring on top, so back and front sleepers get the same no-sink feel wherever they lie.
- An affordable route to more space: Coolflex sits at the budget end of the market, so upgrading to a UK king here costs less than it would with most brands.
This size suits you if...
You share the bed every night and a double has started to feel cramped, especially with a firm mattress where you settle into your own spot rather than rolling to the middle. Or one of you is approaching six foot and keeps waking with feet at the edge. It also suits couples on mismatched schedules who want the springs, and the space, to absorb early alarms.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king, or you sleep alone. In either case we'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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FAQ's
Is a UK king big enough for a couple on a firm mattress?
Yes, comfortably for most. You get 75cm each for two people sharing, and because this is an extra firm mattress you stay on your own side rather than drifting into a dip in the middle. If one of you is broad-shouldered or you share with a dog who claims a corner, the UK super king adds another 30cm of width.
Will the Coolflex Lux Ortho Pocket king help if my partner gets up earlier than me?
It should, on two counts. The pocket springs move independently, so someone climbing out at 5am sends far less movement across the bed than a mattress that flexes as one piece. And the width of a UK king means you were never sleeping close enough to feel every shift in the first place.
Is the UK king long enough for someone over six foot?
At 200cm, the UK king is 10cm longer than the UK Double, and for many taller sleepers that length is the real reason to upgrade. It means your feet stay on the mattress rather than hanging off the end. Sizing up further to the UK super king adds width only; the length is the same.
What room size does the Coolflex Lux Ortho Pocket king need?
We suggest at least 2.7m x 2.9m, and that assumes you still want to walk round the bed and open wardrobe doors. New build master bedrooms can be tighter than they first appear once furniture goes in, so measure the floor with everything in place. If the room falls short, the UK double needs at least 2.6m x 2.8m.
How much bigger is the king than the double in this mattress?
The UK king is 15cm wider and 10cm longer than the UK Double. The width works out at 75cm each for two people sharing, and on an extra firm mattress like this one, where you sink in very little, that personal space is something you notice every night rather than a number on a spec sheet.