Harrison Spinks Platinum 12500 Pocket Mattress (Medium Feel)
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Mattress
Harrison Spinks Platinum 12500 Pocket Mattress (Medium Feel)
Size
Firmness
Medium
Construction
Pocket Spring
Wool
Natural
Depth (cm)
29
Layers
5
Layer Details
Comfort layer
Layers of plush British wool sit at the top, which means natural temperature regulation. You should feel cosy in winter and refreshed in summer.
Comfort layer blend
Cotton and wool fibres are blended with hardwearing hemp and flax. These tougher natural fibres help the comfort layers keep their feel for longer.
Sustainable layer
A layer of Ecotex fibres, made from recycled materials, completes the comfort section. It adds strength and durability rather than softness.
Support system
Layers of 10,500 mini springs contour to your body for personalised comfort. An additional 1,000 Posturfil springs respond to your movements and weight distribution.
Spring system
The base uses 1,000 Cortec Quad Revolution springs, each encased in its own pocket and secured into groups of four. Each of these springs contains a mini spring inside it, adding a second stage of response.
Layer details from mattressonline.co.uk product page, September 2026.
- Room to sleep apart, together: With 75cm each for two people sharing, you both get a proper stretch of that wool-topped surface without drifting into each other's half.
- Less disturbance when schedules clash: The individually pocketed springs respond only where you press, so a partner leaving hours before you is less likely to wake you across this wider surface.
- Length for taller sleepers: At 200cm, the UK king is 10cm longer than the UK double, which means anyone approaching 6ft finally keeps their feet on the mattress.
- Natural fillings across a bigger footprint: British wool, cotton, hemp and flax regulate temperature across the full 150cm width, useful when two bodies are generating heat under one duvet.
- Space for real life: Propping pillows during pregnancy, easing in and out after an injury, or a dog claiming a corner: the extra 15cm over a UK double absorbs all of it.
This size suits you if...
You share the bed every night and a double has started to feel like a compromise, one of you keeps different hours and you want their comings and goings to register less, or someone in the bed is tall enough that the extra 10cm of length matters as much as the width. It also suits couples whose room comfortably clears our suggested 2.7m x 2.9m minimum.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king, which is common in new build masters once wardrobes go in. We'd recommend the UK double instead, which needs at least 2.6m x 2.8m.
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Is the UK king Harrison Spinks Platinum 12500 big enough for a couple?
Yes, comfortably for most. The UK king gives 75cm each for two people sharing, and the layered pocket spring system means each side responds to its own sleeper rather than the pair of you. If one of you sprawls, shares with a dog, or simply wants more, the UK super king adds another 30cm of width.
Will a king size Platinum 12500 stop me feeling my partner move?
It helps on two fronts. Every spring in the Cortec Quad Revolution system sits in its own pocket, so movement stays local rather than travelling across the bed, and the UK king's 150cm width puts more distance between you than a double would. No mattress removes disturbance entirely, but this size and construction together reduce it noticeably.
Is the UK king Platinum 12500 long enough for someone over 6ft?
At 200cm, or 6ft 6in, it gives most tall sleepers room to spare, and it is 10cm longer than the UK double as well as 15cm wider. If length is your main reason for upgrading, note that the UK super king is the same length as the UK king, so sizing up beyond this buys width, not extra legroom.
What room size does a king Platinum 12500 need?
We suggest at least 2.7m x 2.9m, with around 3.2m x 3.2m feeling comfortable once wardrobes and bedside tables are in. That guidance is ours, not the manufacturer's. If your room is tighter, the UK double needs at least 2.6m x 2.8m and still suits most couples.
Should I buy the Platinum 12500 in a UK king or a UK super king?
Choose the UK king if your room sits near the 2.7m x 2.9m minimum we suggest, or if the double-to-king step already feels generous. The UK super king is 30cm wider, the same length, and we suggest at least 3m x 2.9m for it, so it rewards couples with a genuinely large room.