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
Pocket Spring
Wool
Natural
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.
- Real width for one sleeper: At 120cm across, it's 30cm wider than a UK single, which means a solo sleeper can turn, stretch and change position without meeting the edge.
- Fits rooms a double cannot: It's 15cm narrower than a UK double, so it works in box rooms, loft conversions and compact second bedrooms where a 4ft 6in frame would block the walkway.
- Springs suited to solo sleeping: With 12,500 springs in total, the surface responds to one body precisely, which suits a lighter solo sleeper who wants that gently cradled, soft to medium feel.
- Wool comfort in a smaller room: British wool at the top wicks moisture and regulates temperature, useful in compact or loft rooms that run warm in summer.
- Standard 4ft bedding and frames: The small double is a standard UK size, so fitted sheets and frames are easy to find, and a standard double duvet covers it comfortably.
This size suits you if...
You sleep alone, prefer a soft, cushioned surface and have outgrown a UK single, or your bedroom is too tight for a UK double but you still want a bed guests can occasionally share. It also fits a guest room or holiday let where the odd couple stays but nobody sleeps there nightly. Allow at least 2.4m x 2.8m of floor space.
Consider another size if...
You share the bed every night, since two adults on 120cm of soft to medium mattress will feel each other constantly. We'd recommend the UK double instead, which is 15cm wider and the same length; allow at least 2.6m x 2.8m for it.
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What size is the Harrison Spinks Platinum 12500 in a UK small double?
It measures 120 x 190cm, which is 4ft x 6ft 3in. That's the same length as a UK double but 15cm narrower, so it gives a solo sleeper generous width while still fitting rooms that a standard double would crowd. We suggest a room of at least 2.4m x 2.8m.
Is a UK small double big enough for a couple on this mattress?
For occasional nights, yes. Two adults can share 120cm for a guest stay or the odd weekend, but as an everyday bed for a couple the width becomes limiting, and the soft to medium feel means you'll notice each other more. Couples sharing nightly would be better served by the UK double, which is 15cm wider.
Will the small double fit in a box room or loft conversion?
Often, and that's its main advantage. Being 15cm narrower than a UK double, it leaves walking space in rooms where a bigger bed would touch the wall or stop the door clearing. Measure first: we suggest a minimum floor space of 2.4m x 2.8m for a UK small double.
Is the Harrison Spinks Platinum 12500 small double good for a teenager?
It can be a sensible step up from a UK single, since the small double adds 30cm of width at the same length without claiming much more floor space. The soft to medium feel suits lighter sleepers, which many teenagers are, though a heavier teen who prefers a firmer surface may find it a little too yielding.
Where can I compare prices for this mattress in a small double?
Use the live table on this page. The prices shown here are updated as retailers change them, so it's the quickest way to see current UK small double pricing for the Platinum 12500 without checking each retailer yourself.