Harrison Spinks Diamond 25000 Pocket Small Double 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
£2,829
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Harrison Spinks Diamond 25000 Pocket Mattress (Firmer Feel)
More available sizes
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
- Real room to spread out alone: At 120cm wide, this size gives a solo back or front sleeper generous space to shift position, which suits the firm surface this mattress is built around.
- Fits rooms a double cannot: The UK small double is 15cm narrower than the UK Double, which can be the difference between a door clearing and a room feeling cramped.
- A sensible guest room choice: Two people can share for occasional stays, and the independent pocket springs limit the ripple one guest feels when the other turns over.
- Standard 4ft footprint: Because 4ft is a common UK size, frames and fitted sheets are easy to find, so a premium mattress does not leave you hunting for bedding.
- Firm support in a compact size: The catalogued firm feel means a smaller mattress does not mean a softer one, useful if you sleep alone but want proper spring-led support.
This size suits you if...
You're a solo adult who has outgrown a UK single and wants space to stretch, but your bedroom, loft room or studio cannot take a full double footprint. It also suits a guest room where couples stay occasionally rather than nightly, or a downsized home where the bed has to fit the new room rather than the old one.
Consider another size if...
You share the bed every night, because 120cm is tight for two on a regular basis. We'd recommend the UK double instead, which is 15cm wider; allow at least 2.6m x 2.8m of floor space for it.
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FAQ's
Is a small double big enough for the Diamond 25000's firm feel to work for one person?
Yes. A firm mattress rewards space to move, and at 120 x 190cm a solo back or front sleeper has plenty. The pocket springs respond to your shape rather than pushing back as one surface, so the extra 30cm of width over a UK single is genuinely usable, especially if you tend to sprawl.
Can a couple share the Diamond 25000 in a UK small double?
For occasional nights, yes, which makes it a workable guest room option. The independent pocket springs help mask a partner's movement. For nightly sharing, 120cm is snug for two adults, and we'd point you to the UK double or UK king pages of this mattress instead.
What room size do I need for a small double mattress like this?
We suggest allowing at least 2.4m x 2.8m. That leaves enough space to walk round the bed and open drawers, which matters in the box rooms and loft conversions this size is usually bought for. Measure the room empty, and check door clearance too, since width often decides whether a 4ft frame fits.
How does the small double compare to the single and double in this range?
The UK small double is 30cm wider than the UK single and the same length, so you gain sleeping space without a longer bed. It's 15cm narrower than the UK double, again the same length. In practice that makes it the middle option: more room for one, less demanding on the floor plan.
Where can I buy the Diamond 25000 in a UK small double?
Compare the retailers listed on this page; the prices shown here are updated as retailers change them. One thing to confirm when ordering: this model is sold in more than one firmness, so check with the retailer that you're getting the firmer feel version in the small double size.