Coolflex Hybrid CHILL Mattress
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Mattress
Coolflex Hybrid CHILL Mattress
Size
Firmness
Medium
Construction
Foam
Pocket Spring
Hybrid
Memory Foam
Depth (cm)
37
Layers
4
Layer Details
Pillow Top
A plush pillow top with up to 1200 mini pocket springs, working like a stitched-in mattress topper. You get that soft, cushioned first touch without needing to buy a separate topper.
Cool Gel Memory Foam
Memory foam infused with gel microbeads to regulate temperature and improve breathability, designed to draw heat away from the body. In practice, that means the contouring feel of memory foam with less heat build-up overnight.
Comfort Foam
Layers of Comfort Foam that cradle pressure points and relieve pressure across the whole body. Side sleepers should notice this most around the hips and shoulders.
Pocket Springs
Up to 800 individually pocketed springs that move independently to target support where you need it and keep your spine aligned. Independent movement also means less disturbance when a partner shifts position.
Layer details from mattressnextday.co.uk product page, September 2026.
- Room for two in a normal-sized bedroom: At 135 x 190cm it gives a couple a proper shared bed while leaving space for wardrobes and drawers in an average UK room.
- 67.5cm per sleeper: Two people sharing get 67.5cm each, which most couples find comfortable, although restless or broader sleepers may want more.
- Cooling matters more when you share: Two bodies generate more heat than one, so the gel-infused memory foam's job of drawing warmth away counts for more in a shared double.
- Less partner disturbance: The individually pocketed springs move independently, which means one of you turning over is less likely to wake the other.
- Easy to dress: Standard double sheets and duvets fit, though at 37cm deep you should check your fitted sheets are deep enough.
- Bedside tables can stay: Allow at least 2.6m x 2.8m and most rooms will still take a table on each side, which a UK king often rules out.
This size suits you if...
You share the bed every night and your room is a typical UK size, you're furnishing a first flat or a shared bedroom and want the safe, standard couples' size, or you sleep hot alongside a partner and want cooling without giving up a soft, cushioned feel.
Consider another size if...
You and your partner both like space, one of you is a restless sleeper, and your room measures at least 2.7m x 2.9m. In that case we'd recommend the UK king instead, which is 15cm wider and 10cm longer.
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Is the Coolflex Hybrid CHILL double big enough for a couple?
For most couples, yes. The UK double gives 67.5cm each for two people sharing, which is the long-standing standard for shared beds. The pocket springs also reduce movement transfer between you. That said, if either of you is broad-shouldered or restless, the UK king's extra 15cm of width is a meaningful upgrade where the room allows.
What room size do I need for a Coolflex Hybrid CHILL double?
We suggest at least 2.6m x 2.8m for a UK double, with around 3m x 3m the comfortable norm. The 135 x 190cm footprint leaves room for bedside tables on both sides in most bedrooms, plus a wardrobe and drawers, which is why it remains the default couples' choice in typical UK homes.
Should I get the Coolflex Hybrid CHILL in a double or a king?
It comes down to your room. The UK double is 15cm narrower and 10cm shorter than the UK king, so it suits rooms where a king would dominate. If your bedroom is at least 2.7m x 2.9m and you both value space, size up. If you'd lose a bedside table to fit the king, stay with the double.
Will the double fit up the stairs of an older house?
The Coolflex Hybrid CHILL is a substantial 37cm-deep hybrid, so it's bulkier to carry than a thin foam mattress. A UK double is 4ft 6in x 6ft 3in, which usually manages the turning stairs of older terraces and tight new build landings better than a UK king would. Measure any awkward corners before ordering.
Where can I buy the Coolflex Hybrid CHILL in a UK double?
Compare the retailers listed on this page. The prices shown here are live and updated as retailers change them, so it's worth checking back before you buy rather than relying on a figure you saw last week. Stock of individual sizes can move around, so the double's availability may differ from other sizes.