Harrison Spinks Platinum 12500 Pocket Super King Mattress (Firmer Feel)
The Harrison Spinks Platinum 12500 is a deep, 29cm pocket spring mattress handcrafted in the UK, with 12,500 springs in total working across three separate spring layers.
- Firm feel, no memory foam sink
- Cosy in winter, cooler in summer
- Handcrafted in the UK
£2,299
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Harrison Spinks Platinum 12500 Pocket Mattress (Firmer Feel)
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Mattress details
Mattress
Harrison Spinks Platinum 12500 Pocket Mattress (Firmer Feel)
Size
Firmness
Firm
Construction
Pocket Spring
Wool
Natural
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.
Key benefits
- Space is the real comfort feature: At 6ft wide, distance does what no comfort layer can: a partner who turns all night is simply too far away to wake you.
- Room for the whole household: When a child pads in at 3am, or a large dog treats the bed as routine, 180cm of width means nobody ends up clinging to an edge.
- Springs that respond to each of you: The 12,500 springs across three layers move independently, which means each side adapts to the person on it rather than averaging you both out.
- Wool fillings across a big surface: British wool regulates temperature naturally, useful on a bed this size where two adults, and sometimes more, are generating heat under one duvet.
- Know your room can take it: We suggest a bedroom of at least 3m x 2.9m, so measure before ordering rather than after delivery.
This size suits you if...
You share the bed every night and want the maximum space stocked as standard in the UK, you have children or pets who regularly join you and still want everyone to get a fair share, or one of you is a genuinely restless sleeper and you've realised distance matters more than any filling. Your bedroom comfortably clears our suggested 3m x 2.9m minimum.
Consider another size if...
Your room falls short of the 3m x 2.9m we suggest for a UK super king. We'd recommend the UK king instead: it's 30cm narrower but the same length, and needs a smaller room, at least 2.7m x 2.9m by our guidance.
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FAQ's
What size is the Harrison Spinks Platinum 12500 in a UK super king?
It measures 180 x 200cm, or 6ft x 6ft 6in. That makes it the widest size the Platinum 12500 comes in, and 10cm longer than the UK single, small double and double, so taller sleepers get extra legroom as well as width.
What size room do I need for the Platinum 12500 super king?
We suggest a room of at least 3m x 2.9m. That's our own guidance, allowing space to walk around the bed and open drawers or wardrobe doors. In a smaller room the mattress will physically fit, but the room stops working. Loft conversions need extra thought, since the slope often decides which wall takes the bed.
How much space do two people get on a super king?
90cm each for two people sharing, the same width per person as a UK single. Combined with the independent movement of the 12,500 pocket springs, that means one of you turning over is unlikely to disturb the other, either through motion or by simply being close.
Should I choose the Platinum 12500 in a UK king or super king?
The UK super king is 30cm wider than the UK king; the two are the same length. If children or pets join you regularly, or one of you sleeps restlessly, the extra width is what you'll notice most. If your room is under 3m x 2.9m, the UK king is the sensible call.
Is the super king Platinum 12500 firm enough for a couple?
Treat the name with caution: despite 'Firmer Feel', this model is listed as a soft to medium. Across a super king, the three spring layers respond to each sleeper's weight separately, so partners of different builds get individual support, but a heavier sleeper wanting a properly firm surface may find it too yielding.