Harrison Spinks Diamond 25000 Pocket Double Mattress (Medium Feel)
The Harrison Spinks Diamond 25000 is a pocket spring mattress in a medium feel, which means it aims to balance cushioning with support rather than sitting at either extreme.
- Medium feel suits back & side sleepers
- Individually responsive springs
- From a long-established British maker
£2,829
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Harrison Spinks Diamond 25000 Pocket Mattress (Medium Feel)
More available sizes
Mattress details
Mattress
Harrison Spinks Diamond 25000 Pocket Mattress (Medium Feel)
Size
Firmness
Medium
Construction
Pocket Spring
Wool
Natural
Depth (cm)
Layers
6
Layer Details
Cortec Quad pocket springs
The core has 700 Cortec Quad springs, held in groups of four within a single fabric pocket, in a glue-free design. This gives the mattress its supportive base while each group can still respond to your body on its own.
Mini pocket springs
Layers of 24300 mini springs sit above the core and give more points of contact with your body. That means the surface can follow your shape more closely.
British wool comfort layers
Layers of British wool add snug, cushioned comfort over the springs. They soften the feel without relying on foam.
Wool, mohair and cashmere layer
A layer of wool, mohair and cashmere is added to enhance the indulgent feel. You should notice it as a softer, more cosseting surface.
Wool, hemp and flax layer
A blend of British wool, hemp and flax fibres increases durability within the comfort layers. The aim is to help the mattress keep its feel as it is used.
Cotton, hemp and flax layer
Additional layers of cotton, hemp and flax fibres wick away moisture. That should help the mattress feel drier and fresher through the night.
Layer details from harrisonspinks.co.uk and mattressonline.co.uk product pages, October 2026.
Key benefits
- Made for sharing: Pocket springs move independently, which means at 67.5cm each for two people sharing, a partner turning over is far less likely to wake you.
- Fits typical UK bedrooms: We suggest a room of at least 2.6m x 2.8m, which leaves space for a wardrobe and drawers in most doubles.
- Room for bedside tables: At 4ft 6in x 6ft 3in, this size usually still allows a bedside table on each side, something a UK king can rule out.
- Medium feel suits mixed preferences: Couples rarely agree on firmness, and a medium sits between the extremes, which makes it a sensible middle ground for two sleepers.
- Easiest size to move in: The UK double is 15cm narrower and 10cm shorter than the UK king, a real advantage on the turning stairs of older terraced houses.
This size suits you if...
You share the bed every night and want the traditional couples' size rather than something that dominates the room, your bedroom sits around the 2.6m x 2.8m minimum we suggest and you'd like tables on both sides, or you sleep alone and want proper space to spread out, perhaps with a dog or cat claiming a corner.
Consider another size if...
You and your partner keep waking each other or ending up shoulder to shoulder on 67.5cm each. We'd recommend the UK king instead: it's 15cm wider and 10cm longer, and we suggest a room of at least 2.7m x 2.9m for it.
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FAQ's
Is the Harrison Spinks Diamond 25000 double big enough for a couple?
For most couples, yes. The UK double is 135cm wide, giving 67.5cm each for two people sharing, and the pocket spring construction reduces the disturbance you feel when a partner moves. Taller or broader couples, or restless sleepers, may prefer the extra 15cm of width the UK king offers.
What room size do I need for the Diamond 25000 in a UK double?
We suggest at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That smaller minimum usually leaves room for a wardrobe, a chest of drawers and bedside tables on both sides, which is why the UK double remains the default choice for typical British bedrooms.
Should I buy the Diamond 25000 in a double or a king?
Choose the UK double if your room is close to our suggested 2.6m x 2.8m minimum or you want furniture around the bed. The UK king is 15cm wider and 10cm longer, better for couples who feel squeezed, but we suggest at least 2.7m x 2.9m of room for it.
Will a UK double mattress fit up narrow stairs in an older house?
A UK double is one of the easier sizes to manoeuvre, at 135 x 190cm it's 45cm narrower than a UK super king. That said, a deep pocket spring mattress doesn't fold like foam, so measure your stairwell and any tight landings before ordering, particularly in older terraces.
Where can I buy the Diamond 25000 in a UK double?
Compare the retailers listed on this page. The prices shown here are updated as retailers change them, so it's worth checking back before you commit, especially on a premium mattress like this where the gap between offers can be significant.