Harrison Spinks Diamond 25000 Pocket Super King Mattress (Firmer Feel)
The Harrison Spinks Diamond 25000 is a firm pocket spring mattress whose springs move independently, so it responds to your shape and limits the ripple when a partner shifts.
- Firm feel for back & front sleepers
- Tends to sleep cooler than all-foam
- Supportive pocket sprung surface
£3,929
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Harrison Spinks Diamond 25000 Pocket Mattress (Firmer Feel)
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Mattress details
Mattress
Harrison Spinks Diamond 25000 Pocket Mattress (Firmer Feel)
Size
Firmness
Firm
Construction
Pocket Spring
Wool
Natural
Depth (cm)
Layers
6
Layer Details
Wool and viscose
The top layers are a blend of British wool and viscose. This is the first thing you feel when you lie down, so it sets the soft, natural surface over the springs beneath.
Wool and mohair
A British wool and mohair blend sits below. It adds another natural layer of cushioning between you and the spring unit.
Cashmere
A cashmere layer comes next. It adds a soft natural fibre to the mix, so the surface feels less stark than a firm spring mattress might suggest.
Yorkshire wool, silk and British wool
This layer blends Yorkshire wool, silk and British wool. It continues the all-natural filling, adding to the comfort layers that sit over the springs.
Wool, hemp and flax
A British wool, hemp and flax blend that increases durability and breathability. For you, that means a filling that should hold up well over time and let air move through.
Cotton, hemp and flax
A cotton, hemp and flax blend that wicks away moisture. It helps keep the sleeping surface drier, which is useful if you sleep warm. Hemp and flax fibres are also hypoallergenic and antimicrobial.
Layer details from harrisonspinks.co.uk and mattressonline.co.uk product pages, October 2026.
Key benefits
- 90cm of width each: Two people sharing get 90cm each, which means you can stretch out fully without negotiating over the middle of the bed.
- Distance plus independent springs: Pocket springs limit ripple when a partner moves, and at this width there is simply more space between you, so restlessness travels less far.
- Room for the whole household: When children appear at 3am or the dog treats the bed as routine, a super king keeps everyone's share of the mattress workable.
- Firm support across a wide surface: The catalogued firm feel suits back and front sleepers, and the extra width means each of you sits on your own supportive zone rather than rolling together.
- Fills a large master properly: In a period property or a big new master bedroom, a UK king can look undersized; the UK super king holds its own visually as well as practically.
This size suits you if...
You share the bed every night with a partner who fidgets and want distance as well as spring independence, you regularly have children or pets joining you and need everyone to keep a fair share, or you have a large master bedroom where a smaller bed would look lost. You should also allow at least 3m x 2.9m of floor space.
Consider another size if...
Your bedroom falls short of the 3m x 2.9m we suggest, or a firm mattress this wide overwhelms the room. We'd recommend the UK king instead: it is 30cm narrower, the same length, and needs at least 2.7m x 2.9m.
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FAQ's
How much space do two people get on a super king Diamond 25000?
You get 90cm each for two people sharing, the same width as a UK single apiece. Combined with the pocket springs, which compress under one sleeper without dragging the other side down, it means a partner turning over is felt far less than on a narrower bed.
What room size do I need for the Diamond 25000 in a UK super king?
We suggest at least 3m x 2.9m so you can walk round the bed and open drawers comfortably. The mattress itself is 180 x 200cm, so a room at the minimum will still feel dominated by the bed. In a genuinely large master it sits far more naturally.
Is the super king worth it over the UK king for this mattress?
If a restless partner is your problem, yes. The UK super king is 30cm wider than the UK king at the same length, and that extra width does more for undisturbed sleep than any comfort layer can. If your room is under 3m x 2.9m, the UK king is the sensible pick.
Will a super king Diamond 25000 be difficult to get upstairs?
It can be. A pocket spring mattress at 180 x 200cm cannot be rolled or folded the way foam can, so measure your stairwell, landing turns and door swing before ordering. Tight Victorian staircases and loft conversions are the usual sticking points, so check the route first.
Is a firm super king a good choice for co-sleeping with children?
It works well. The firm surface keeps adults properly supported near the edges when a child claims the middle, and 90cm each for two sharing means a small visitor squeezes rather than evicts you. Lightweight side sleepers, including older children, may find the firmness a little unforgiving though.