Kaymed Heavy Sleeper 1200 Pocket Hybrid King Size Mattress
The Kaymed Heavy Sleeper 1200 Pocket Hybrid is a firm hybrid mattress built around 1,200 pocket springs topped with high density reflex foam, which means a supportive, stable feel rather than a soft sink-in one.
- Firm feel for heavier sleepers
- Helps keep your spine aligned
- Durable high-density foam
£909
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Kaymed Heavy Sleeper 1200 Pocket Hybrid Mattress
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Mattress details
Mattress
Kaymed Heavy Sleeper 1200 Pocket Hybrid Mattress
Size
Firmness
Firm
Construction
Foam
Pocket Spring
Hybrid
Orthopaedic
Depth (cm)
33
Layers
3
Layer Details
Knitted cover
A soft knitted finish that adds a touch of cosiness and warmth on the surface. It's designed to help with airflow and breathability too, which matters on a firmer mattress where you sleep more on top than in it.
Reflex Foam
A layer of high density reflex foam that supports spinal alignment, which means your back stays in a healthier position through the night. It's firm and durable rather than plush, so expect a solid feel from the first night.
Pocket Springs
1,200 individual springs, each encased in its own cloth pocket, adapt to your movement independently. That gives personalised support to different parts of your body and helps limit motion transfer from a partner.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- Proper space for two: At 75cm each for two people sharing, the UK king gives each of you a clear stretch of that firm, stable surface.
- Less partner disturbance: The 1,200 pocket springs respond independently, so one of you getting up early is far less likely to wake the other.
- Length for taller sleepers: At 200cm long, the UK king is 10cm longer than the UK double, a real relief if either of you is approaching six foot.
- Firm feel spread wide: High density reflex foam keeps the surface consistent edge to edge, so the extra width is all usable rather than a softer border.
- Substantial presence: The 33cm depth on a 150cm wide frame gives the bed a solid, hotel-style look that suits a decent-sized master bedroom.
This size suits you if...
You share the bed every night and a UK double has started to feel cramped, especially if one of you keeps different hours and the other is a light sleeper. It also fits if either partner is tall and needs the 200cm length, or you're both heavier sleepers wanting firm support with room to spread out.
Consider another size if...
Your bedroom is smaller than the 2.7m x 2.9m we suggest as a minimum for a UK king. In that case we'd recommend the UK double instead, which needs at least 2.6m x 2.8m and keeps the same firm feel.
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FAQ's
Is a UK king big enough for a couple on a firm mattress?
Yes, comfortably for most. The UK king gives 75cm each for two people sharing, and because this is a firm mattress you lie on the surface rather than nestling into a dip, so that width stays usable. If you both roll around a lot, the UK super king adds another 30cm of width.
Will the Kaymed Heavy Sleeper 1200 in a UK king stop me feeling my partner move?
It should help noticeably. The 1,200 pocket springs are individually pocketed, so movement on one side is absorbed rather than passed across, and the width of the UK king means you're rarely lying close enough to feel it anyway. If one of you gets up hours before the other, that combination is exactly what you want.
What room size do I need for a king size Kaymed Heavy Sleeper?
We suggest at least 2.7m x 2.9m, with more feeling comfortable once wardrobes and bedside tables are in. New build master bedrooms can be tighter than they look on the plans, so measure with furniture in mind. If the room falls short, the UK double needs at least 2.6m x 2.8m.
Is the UK king long enough for someone over six foot?
At 200cm, yes for most people. That's 10cm longer than the UK double, which is often the deciding factor for taller sleepers whose feet reach the end of a standard-length bed. The UK super king is the same length, so sizing up beyond a UK king buys you width, never extra length.
Where can I buy the Kaymed Heavy Sleeper 1200 in a UK king?
Availability for this size changes, so the best approach is to compare the retailers listed on this page. The prices shown here are updated as retailers change them, which matters on a mattress at this price point where offers come and go.