Harrison Spinks Diamond 25000 Pocket 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
- A footprint most bedrooms can take: At 135cm wide, the UK double fits comfortably in rooms where the UK king would crowd everything else out.
- Room for bedside tables on both sides: In a typically sized room, the double usually leaves space for a table each side, which a wider bed often sacrifices.
- Firm support that suits sharing: Pocket springs move independently, so when your partner turns over on their 67.5cm of the bed, you feel less of it.
- Easier to get upstairs: A pocket spring mattress of this quality is heavy and doesn't fold, so the double's smaller size helps on the turning stairs of older terraces.
- Bedding is simple: Double sheets and a 200 x 200cm double duvet are stocked everywhere, at every price point.
This size suits you if...
You share the bed every night and your room sits comfortably above our suggested 2.6m x 2.8m minimum, or you sleep alone and want space to spread out on a firm surface. It also suits a guest room that hosts visiting couples, where a premium firm mattress will please back and front sleepers without swallowing the room.
Consider another size if...
You and your partner both like space, one of you is broad shouldered, or a pet claims a corner most nights. At 67.5cm each you may feel squeezed, so we'd recommend the UK king instead, allowing at least 2.7m x 2.9m of room.
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FAQ's
Is a UK double big enough for two people on a firm mattress?
It works for most couples, though 67.5cm each is less personal space than a UK king offers. A firm feel helps here: you're less likely to roll toward the middle, and the pocket springs limit how much movement travels across the bed. Larger sleepers, or couples used to more room, may prefer the UK king.
Will the double Diamond 25000 fit up a narrow staircase?
It should be the most manageable couples' size to move. A traditional pocket spring mattress like this arrives full size rather than rolled, so it can't be folded round a tight landing. At 135 x 190cm the double is easier to turn on older terraced stairs than the UK king, but measure your tightest corner first.
What room size do I need for the Diamond 25000 in a double?
We suggest at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That allows walking space on both sides and, in most rooms, a bedside table each side, something the wider UK king often forces you to give up in a typical British bedroom.
Should a couple choose the double or size up to the UK king?
The UK double is 15cm narrower and 10cm shorter than the UK king. Choose the double if your room is modest or you like sleeping close; choose the UK king if either of you is tall, restless or simply wants more space, and your room meets our suggested 2.7m x 2.9m minimum for it.
Is the double a good choice for a guest room?
Yes, if the room clears our suggested 2.6m x 2.8m minimum. It sleeps visiting couples without dominating the space, and the firm, spring-led feel tends to suit a range of guests who sleep on their backs or fronts. It's a premium spend for occasional use, so weigh that against how often the room is slept in.