Harrison Spinks Platinum 12500 Pocket Mattress (Soft to Medium Feel)
Mattress
Harrison Spinks Platinum 12500 Pocket Mattress (Soft to Medium Feel)
Size
Firmness
Medium Soft
Construction
Depth (cm)
29
Layers
5
Layer Details
- Comfort Layer. Plush British wool sits at the top, which means natural temperature regulation. Wool wicks moisture, so you stay cosy in winter and cooler in summer.
- Comfort Blend. Cotton and wool fibres are blended with hemp and flax. These tougher plant fibres help the comfort layers keep their shape over time.
- Sustainable Layer. A layer of Ecotex fibres made from recycled materials. It's there for strength and durability rather than softness.
- Support System. 10,500 mini springs contour closely to your body, backed by 1,000 Posturfil springs that flex with your movements and weight distribution. This is where the personalised, cradling feel comes from.
- Spring System. At the base, 1,000 Cortec Quad Revolution springs sit in individual pockets, secured in groups of four, with a mini spring inside each one. That layered spring-within-a-spring design gives progressive support as you sink in.
Layer details from mattressonline.co.uk product page, September 2026.
- 75cm each, every night: Two sharers get 75cm each, which means you can settle into your own side of the springs without negotiating for the middle.
- Less partner disturbance: Thousands of individually pocketed springs respond to each sleeper separately, so an early alarm on one side transfers less movement to the other.
- Extra length for taller sleepers: The UK king is 10cm longer than the UK double, a difference anyone approaching six foot will feel at their feet.
- 15cm wider than a UK double: That extra width is where a soft to medium mattress pays off for couples, since each of you sinks into your own cradled patch.
- Cooler across a bigger surface: British wool and a foam-free build breathe well, and the wider footprint means less shared body heat pooling between you.
This size suits you if...
You share the bed every night and a double has started to feel cramped, especially with one of you waking or leaving hours before the other. It also suits couples where one partner is approaching six foot, since the 200cm length removes the dangling-feet problem, or households where the dog has claimed a corner of the bed and shows no sign of giving it back.
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. 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 Harrison Spinks Platinum 12500 UK king big enough for a couple?
Yes, comfortably. At 150cm wide it gives two sharers 75cm each, and the individually pocketed springs mean each of you gets support tuned to your own weight rather than an average of the pair. If you're both broad or simply want more sprawl, the UK super king is 30cm wider.
What room size do I need for the Platinum 12500 in a UK king?
We suggest a room of 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 a floor plan, so measure the actual clear floor space before committing to this size.
Will the UK king suit a sleeper over six foot?
It's a strong fit. The UK king is 10cm longer than the UK double at 200cm, which is often the difference between feet on the mattress and feet hanging off it. On a soft to medium surface like this one, that full-body contact matters for even pressure relief.
Does a UK king reduce partner disturbance on this mattress?
It helps on two fronts. The width gives each of you your own zone, and the pocket spring construction, with springs moving independently, limits how much motion crosses the bed. If one of you gets up hours before the other, the sleeper left behind feels less of it.
Where can I compare prices for the Platinum 12500 in a UK king?
Use the retailer table on this page. The prices shown here are updated as retailers change them, so it's a more reliable guide than a figure written into the text. Availability of this size can shift too, so check back if it's out of stock.