Coolflex Premium Memory Hybrid King Size Mattress
The Coolflex Premium Memory Hybrid is a 32cm deep hybrid with a built-in pillow top, cool gel memory foam and 800 pocket springs, rated Medium Firm.
- Pillow top doubles as a topper
- Cool gel foam draws heat away
- Reinforced edges, use the full width
£379
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Coolflex Premium Memory Hybrid Mattress
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Mattress details
Mattress
Coolflex Premium Memory Hybrid Mattress
Size
Firmness
Medium Firm
Construction
Foam
Pocket Spring
Hybrid
Memory Foam
Orthopaedic
Depth (cm)
32
Layers
4
Layer Details
Pillow Top
A plush pillow top acts as a built-in mattress topper, filled with Comfort Foam layers. In practice this gives you extra cushioning and pressure relief the moment you lie down.
Cool Gel Memory Foam
A generous layer of Cool Gel Memory Foam actively draws heat away from the body for a cooler sleep. It also gently moulds to your body shape, which means personalised pressure relief at your hips and shoulders.
Pocket Springs
High tensile steel pocket springs sit in individual fabric pockets and move independently. That means the mattress adapts to changes in your weight distribution through the night, and you feel less of your partner's movement.
Reinforced Edge Springs
An outer ring of firmer pocket springs reinforces the edges. You can sleep or sit right at the side without the mattress sagging away beneath you.
Knitted Cover
A knitted cover finishes the mattress. It is hypoallergenic and vegan friendly, useful if allergies are a concern.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Space that actually reduces disturbance: With 75cm each for two people sharing, plus 800 independently moving pocket springs, a partner turning over is further away and felt less.
- Extra length for taller sleepers: At 200cm long, the UK king is 10cm longer than the UK double, which matters more than the width if one of you is nudging six foot.
- Usable width right to the edge: The reinforced edge springs mean the 150cm width is all sleepable, so neither of you feels tipped off the side after claiming your half.
- Cool sleeping across a shared bed: Two bodies generate more heat than one, and the cool gel memory foam draws that warmth away rather than trapping it between you.
- A shared bed without a shared wake-up: If one of you leaves for work hours before the other, the pocket springs and the wider gap between you make the early exit easier to sleep through.
This size suits you if...
You share the bed every night and a double has started to feel like negotiated territory, especially if one of you tosses and turns or gets up much earlier than the other. It also suits taller couples, since the 200cm length gives anyone approaching six foot room to stretch out. If a dog has become a permanent fixture on the bed, the extra width absorbs that too.
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 and the width would go unused. We'd recommend the UK double instead, which needs a smaller room at 2.6m x 2.8m.
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FAQ's
Is a UK king Coolflex Premium Memory Hybrid big enough for a couple?
Yes, comfortably for most. At 150 x 200cm you get 75cm each for two people sharing, and because the 800 pocket springs move independently, that extra distance between you translates into genuinely less disturbance when one of you shifts or gets up early. Couples who want still more space could consider the UK super king, which is 30cm wider.
How much bigger is the UK king than the double in this mattress?
The UK king is 15cm wider than the UK double and 10cm longer. The width is what most upgrading couples notice night to night, but the length is the quieter win: at 200cm, the UK king suits anyone approaching six foot who finds their feet at the end of a 190cm double.
What room size do I need for a king size Coolflex mattress?
We suggest at least 2.7m x 2.9m for a UK king, and that is our guidance rather than Coolflex's. Measure with wardrobes and bedside tables in place before you commit; a new build master bedroom can shrink surprisingly once the furniture is in. If your room is tighter, the UK double needs at least 2.6m x 2.8m.
Is the Coolflex Premium Memory Hybrid UK king good for tall people?
It is one of the better picks in the range for height. The UK king runs 200cm long, the same length as the UK super king and 10cm longer than the UK single, small double and double. If one of you is over six foot, that extra length is arguably the real upgrade here, more so than the width.
What are the dimensions of the Coolflex Premium Memory Hybrid in a UK king?
It measures 150 x 200cm, or 5ft x 6ft 6in. That takes standard UK king sheets and pairs well with a 230 x 220cm king duvet. The 32cm depth is the same across every size of this mattress, so check your fitted sheets have deep enough pockets whichever size you choose.