Harrison Spinks Platinum 12500 Pocket Mattress (Firmer Feel)
Mattress
Harrison Spinks Platinum 12500 Pocket Mattress (Firmer Feel)
Size
Firmness
Firm
Construction
Depth (cm)
29
Layers
6
Layer Details
- Comfort fillings. Layers of plush British wool sit at the top, which means natural temperature regulation. You should feel cosy in winter and cooler in summer.
- Comfort fillings blend. Cotton and wool fibres are blended with hemp and flax. These tougher plant fibres help the comfort layers keep their shape over time.
- Ecotex layer. A layer of Ecotex fibres made from recycled materials. It adds strength and durability rather than a feel you'd notice directly.
- Mini Pocket Springs. Layers of 10,500 mini springs contour to your body. Because each spring moves independently, the surface adapts to your shape for a more personalised feel.
- Posturfil springs. An additional 1,000 Posturfil springs respond to your movements and how your weight is distributed. In practice, this means flexible support that adjusts as you change position.
- Cortec Quad Revolution springs. The base layer of 1,000 Cortec Quad Revolution springs adapts to your body for deeper support. Each one has a mini spring inside it, so you get two stages of response from a single spring.
Layer details from mattressonline.co.uk product page, September 2026.
- Genuine personal space: At 75cm each for two people sharing, the UK king means neither of you sleeps pinned to the edge.
- Independent springs, quieter nights: With 12,500 springs moving individually across three layers, an early riser can slip out with less ripple reaching the other side.
- Length for taller sleepers: The 200cm length gives anyone approaching six foot room to stretch out without their feet meeting the bed frame.
- Wool that regulates for two: British wool fillings help even out temperature, useful when two bodies share one mattress and run at different heats.
- Room to reposition: The extra width is a quiet relief during pregnancy or recovery from surgery, when propping pillows and shifting position happen all night.
This size suits you if...
You share the bed every night and have started to feel a double's limits, one of you gets up hours before the other and you'd like their exit to go unnoticed, or one of you is tall enough that 190cm beds leave feet hanging. Your room can take it too: we suggest at least 2.7m x 2.9m for a UK king.
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 slightly smaller room at 2.6m x 2.8m.
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Is the Platinum 12500 in a UK king good for couples?
Yes, with one caveat. The 150cm width gives 75cm each for two people sharing, and the independent pocket springs limit how much one partner's movement carries across the bed. The caveat is feel: despite the Firmer Feel name, this model is listed as soft to medium, so heavier couples wanting a properly firm surface should think carefully.
Will a UK king Platinum 12500 fit my bedroom?
The mattress itself is 150 x 200cm, or 5ft x 6ft 6in. For the room, we suggest at least 2.7m x 2.9m so you can walk round both sides and open drawers, with more space feeling comfortable rather than tight. New build master bedrooms often shrink once fitted wardrobes go in, so measure the usable floor, not the plan.
Is the UK king long enough for a tall sleeper?
For most people, yes. The 200cm length is 10cm longer than a UK double, which matters once someone is approaching six foot. If length is your reason for upgrading, note that the UK super king is the same length as the UK king, so sizing up beyond king only buys width, not extra legroom.
Does one partner getting up early disturb the other on this mattress?
Less than on many sprung beds. The 12,500 springs across three layers respond independently, so movement on one side transfers weakly to the other, and the 75cm each of a UK king means you're rarely lying close enough to feel it anyway. No spring system removes disturbance entirely, but this combination reduces it noticeably.
Should I choose the UK king or the UK super king in this mattress?
It mostly comes down to your room. The UK super king is 30cm wider than the UK king and the same length, and we suggest at least 3m x 2.9m for it. If you share with a dog or a co-sleeping child, that extra width is genuinely useful; if your room is average sized, the UK king is the safer buy.