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.
- A shared surface with precise support: With 12,500 springs across the 135cm width, each sleeper gets support that responds to their own weight rather than to whoever moved last.
- Fits most UK bedrooms: We suggest allowing at least 2.6m x 2.8m, which most main bedrooms can manage while keeping bedside tables on both sides.
- 67.5cm each for couples: Two people sharing get 67.5cm each, enough for most couples, though restless sleepers may prefer the extra width of a UK king.
- Natural fillings for two body temperatures: British wool wicks moisture and regulates warmth, which matters more in a shared bed where one of you runs hot.
- Easy to dress: Double sheets and duvets are stocked everywhere at every price, so replacing bedding never becomes a hunt.
This size suits you if...
You share the bed every night and your bedroom is a typical UK size, where a UK king would leave little walking space. Or you sleep alone and want proper room to spread out, perhaps with a dog or cat claiming a corner, without giving the bed the whole room. It also makes a comfortable guest room bed for visiting couples.
Consider another size if...
You and your partner both like space and your room measures at least 2.7m x 2.9m. The UK king is 15cm wider and 10cm longer than the UK double, and we'd recommend it for restless or taller sleepers.
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Is the Harrison Spinks Platinum 12500 double big enough for two adults?
For most couples, yes. Two people sharing a UK double get 67.5cm each, and the mattress's 12,500 springs mean each side responds to its own sleeper rather than the whole surface tilting. If either of you is tall or moves a lot at night, the UK king is 15cm wider and 10cm longer.
What room size do I need for the Platinum 12500 in a UK double?
We suggest allowing at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That leaves space to open drawers and keep bedside tables on both sides. This is our guidance rather than the manufacturer's, so measure your own layout before ordering.
Should I get the Platinum 12500 in a double or a king?
The UK double suits typical UK bedrooms and couples happy with 67.5cm each. The UK king is 15cm wider and 10cm shorter than nothing, sorry: 10cm longer, and needs a room of at least 2.7m x 2.9m. If your room allows it and you both value space, size up; if not, the UK double is the balanced choice.
Will the UK double Platinum 12500 fit up a narrow staircase?
At 135 x 190cm and 29cm deep, it's a substantial mattress, and pocket spring builds don't roll or fold the way foam ones can. If you live in an older terrace with a turning staircase or a tight new build landing, measure the route before buying and check the retailer's delivery guidance.
What are the exact dimensions of the Platinum 12500 double?
The UK double measures 135 x 190cm, which is 4ft 6in x 6ft 3in. It's the same length as the UK single and UK small double but 45cm wider than the UK single, so a solo sleeper upgrading from either gains noticeable stretching room without needing a bigger bedroom.