Harrison Spinks Diamond 25000 Pocket Mattress (Soft to Medium Feel)
Mattress
Harrison Spinks Diamond 25000 Pocket Mattress (Soft to Medium Feel)
Size
Firmness
Medium Soft
Construction
Depth (cm)
32
Layers
7
Layer Details
- Comfort Layer - Top Surface (Summer Side). The summer side puts moisture wicking cotton closest to you. In practice that means a cooler, drier feel on warm nights.
- Comfort Layer - Moisture Wicking Blend. Further layers of cotton, hemp and flax fibres draw moisture away from your body. This adds to that refreshing feel rather than letting heat and dampness build up.
- Comfort Layer - Breathability Blend. A blend of British wool, hemp and flax fibres improves durability within the comfort layers. Natural fibres like these tend to hold their loft well over time.
- Comfort Layer - Luxury Blend. Wool, mohair and cashmere sit here to deepen the indulgent feel. These are the fillings that give the surface its soft, expensive-feeling finish.
- Comfort Layer - British Wool. Layers of British wool provide snug, cushioned comfort. Wool also regulates temperature naturally, which helps across the seasons.
- Support Layer - Mini Pocket Springs. 24,300 mini springs create many more points of contact with your body. That means comfort delivered exactly where you need it, with less of the hammocking a coarser spring layer can cause.
- Support Layer - Cortec Quad Springs. 700 of Harrison Spinks' award-winning Cortec Quad springs form the core, secured in groups of four within one fabric pocket. This grouped design gives responsive, stable support at the base of the mattress.
Layer details from mattressonline.co.uk product page, September 2026.
- A shared size for typical rooms: At 135 x 190cm (4ft 6in x 6ft 3in), the UK double fits comfortably in bedrooms where a UK king would leave little walking space.
- Room for bedside tables both sides: Allow at least 2.6m x 2.8m and most couples can still fit a table on each side, which matters more than an extra few centimetres of bed.
- Precise support across a shared surface: The 24,300 mini springs above 700 Cortec Quad springs adapt to each sleeper individually, so a lighter partner isn't rolled towards a heavier one.
- Natural fillings that stay cool for two: Two bodies generate real warmth, and the cotton, wool, hemp and flax layers breathe and wick moisture rather than trapping it.
- Two pairs of hands for the seasonal turn: This is a double-sided design at 32cm deep, and a shared size means someone to help turn it, which genuinely eases the job.
This size suits you if...
You share the bed every night and want the traditional couples' size, or you sleep alone and like space to spread out, perhaps with a dog or cat claiming a corner. It also suits a guest room that hosts visiting couples, provided the room meets our suggested 2.6m x 2.8m minimum and you're happy investing in luxury fillings for occasional use.
Consider another size if...
You and your partner both like room to stretch, or either of you is tall. The UK king is 15cm wider and 10cm longer, and we'd recommend it if your room allows at least 2.7m x 2.9m.
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Is the Diamond 25000 in a UK double big enough for a couple?
It gives 67.5cm each for two people sharing, the long standing UK standard for couples. The mattress helps here: with 24,300 mini springs adapting to each of you separately, movement transfers less across that shared width than a coarser spring layer would allow. If either of you sleeps in a starfish position, though, consider sizing up.
What room size do I need for a UK double Diamond 25000?
We suggest at least 2.6m x 2.8m, which leaves space to walk around the bed and open drawers. That's our own guidance rather than the manufacturer's. In a room around 3m x 3m you'll comfortably fit bedside tables on both sides, which is often the deciding factor between a UK double and a UK king.
Will the UK double Diamond 25000 get up a narrow staircase?
At 135cm wide and 32cm deep, this is a substantial, heavy mattress that won't fold or compress like a boxed foam model. If you live in an older terrace with a turning staircase or a new build with a tight landing, measure the awkward points before ordering and check the retailer's access requirements.
Should I get the Diamond 25000 in a double or a king?
The UK double is 15cm narrower and 10cm shorter than the UK king. If you're both average height and your room is on the smaller side, the UK double is the sensible pick. Taller sleepers, or couples who feel cramped, should take the UK king if the room allows at least 2.7m x 2.9m.
Is the double-sided design hard to manage in a UK double?
This mattress has a summer surface designed for seasonal turning, and at 135cm wide and 32cm deep it's a two-person job. The upside of the UK double as a couples' size is that there's usually someone to take the other end. If you'd be turning it alone, factor that in before buying.