Kaymed Smart Phase 1600 Pocket Hybrid Mattress
Mattress
Kaymed Smart Phase 1600 Pocket Hybrid Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
27
Layers
3
Layer Details
- Smart Phase Foam. A 50mm layer of Kaymed's exclusive Smart Phase foam, infused with microbeads, copper and phase change crystals. It thermoregulates by moving heat away from the mattress surface, absorbing and releasing body heat to keep you at a comfortable temperature.
- Reflex Foam Comfort Layer. A soft, flexible reflex foam that sits between you and the springs. It adds the support needed for good spinal alignment without a hard, boardy feel.
- Pocket Springs Support System. 1600 pocket springs, based on the kingsize mattress, each housed in its own fabric pocket. They react independently to movement through the night, which means the mattress shapes around your body rather than tilting you towards a partner.
Layer details from mattressonline.co.uk product page, September 2026.
- Room to sleep apart, together: At 150 x 200cm the UK king is 15cm wider than the UK double, which means each of you gets space to shift position without a negotiation.
- Springs that keep movement local: The 1600 pocket springs react independently, so if one of you gets up hours before the other, the disturbance stays on their side.
- Length for taller sleepers: The UK king is 10cm longer than the UK double, so anyone approaching six foot stops sleeping diagonally or dangling their feet.
- Cool across the full width: The 50mm Smart Phase foam layer moves heat away from the surface, useful when two bodies are warming one mattress all night.
- Usable right to the edge: The foam encapsulated border supports the perimeter, so the full 75cm each is genuinely sleepable rather than a soft roll-off zone.
This size suits you if...
You share the bed every night and a double has started to feel like a compromise, especially if one of you runs warm or gets up at a different time. It also makes sense if one partner is tall, since the 200cm length is a real improvement over a standard double, or if a dog or child regularly joins you and you need the spare width to absorb them.
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 a room of at least 2.6m x 2.8m.
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Is the Kaymed Smart Phase 1600 UK king good for couples on different schedules?
Yes, and it's arguably the best size of this mattress for that situation. The 1600 pocket springs move independently, so an early riser slipping out won't tilt or bounce the other side, and the 75cm each for two people sharing means you're rarely sleeping close enough to feel it anyway.
What room size do I need for the Kaymed Smart Phase 1600 in a UK king?
We suggest a room of at least 2.7m x 2.9m, with 3.2m x 3.2m feeling comfortable once wardrobes and bedside tables are in. New build master bedrooms can be tighter than they look on the plans, so measure the usable floor rather than the wall-to-wall figure.
Is the UK king long enough for someone over six foot?
At 200cm, the UK king suits most tall sleepers comfortably. That's 10cm longer than the UK double, which is the difference between your feet reaching the edge and clearing it. If you're well over six foot and want more width too, the UK super king is 30cm wider and the same length.
How much space does each person get on this mattress in a UK king?
You get 75cm each for two people sharing, and because the border is foam encapsulated, that width is usable right to the edge rather than tapering off. It's enough for a hot sleeper to spread out away from their partner, which matters slightly less here given the Smart Phase foam's cooling, but still helps.
Should I choose the UK king or the UK super king in this mattress?
The UK king suits most couples: plenty of space without dominating the room. Size up if a pet or child routinely joins you, since the UK super king is 30cm wider than the UK king, though it needs a room of at least 3m x 2.9m. Both are the same 200cm length.