Harrison Spinks Emerald 16500 Pocket Mattress (Medium Feel)
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Mattress
Harrison Spinks Emerald 16500 Pocket Mattress (Medium Feel)
Size
Firmness
Medium
Construction
Pocket Spring
Wool
Natural
Depth (cm)
29
Layers
3
Layer Details
Comfort fillings
Layers of natural British wool, cotton, hemp and flax fibres sit at the sleep surface. One side places wool closer to the top for winter warmth, while the other includes moisture-wicking cotton for summer freshness, so you flip the mattress with the seasons.
Mini Pocket Springs
A layer of 15,800 mini springs delivers bouncy comfort, with the small pockets creating airflow throughout the mattress. They reach areas that broader springs can miss, such as the hips and lower spine.
Support System
At the base, 700 Cortec™ Quad springs are encased in cloth pockets and secured into groups of four. They're highly responsive, providing support based on your unique weight, shape and movement.
Layer details from mattressonline.co.uk product page, September 2026.
- The traditional couples' size: At 135 x 190cm, or 4ft 6in x 6ft 3in, the UK double is the long-standing standard for two people sharing.
- 67.5cm each for two sharing: You each get 67.5cm of width, which is comfortable for most couples, though restless sleepers may want more.
- Fits most UK bedrooms: We suggest a room of at least 2.6m x 2.8m, which leaves space to walk round the bed and open drawers.
- Natural fillings for two warm bodies: Two sleepers generate more heat than one, and the wool, cotton, hemp and flax fillings breathe better than foam does.
- Springs that support each of you: The pocket spring design responds to each sleeper's weight and shape separately, useful when you and your partner are built differently.
This size suits you if...
You share the bed every night and want the size most bedrooms were designed around, or you sleep alone and like room to stretch out, perhaps with a dog or cat claiming a corner. It also suits a guest room that hosts visiting couples, since the UK double keeps the footprint modest while still sleeping two comfortably.
Consider another size if...
You both want more space and your room can take it. We'd recommend the UK king instead: it's 15cm wider and 10cm longer than the UK double, and we suggest a room of at least 2.7m x 2.9m for it.
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Is the Emerald 16500 UK double big enough for a couple?
For most couples, yes. At 135cm wide you get 67.5cm each for two people sharing, and the pocket springs adjust to each sleeper's weight and movement independently, so one partner turning over is less likely to disturb the other. If either of you is broad or a restless sleeper, the UK king adds 15cm of width.
What room size do I need for the Emerald 16500 in a UK double?
Allow at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That guidance is ours rather than the manufacturer's. In a typical room it leaves space for bedside tables on both sides plus a wardrobe, which is one of the main reasons couples choose a UK double over a UK king.
Can one person flip the Emerald 16500 UK double on their own?
You'll want to flip it, because the two sides are designed for different seasons: wool near the surface on one, moisture-wicking cotton on the other. At 135cm wide and 29cm deep with natural fillings, it's a substantial mattress, so we'd suggest two people for the seasonal turn.
How much bigger is the UK king than the UK double?
The UK double is 15cm narrower and 10cm shorter than the UK king. That extra length matters if either of you is tall, since the UK double runs to 190cm, or 6ft 3in. The trade-off is floor space: we suggest at least 2.7m x 2.9m for the UK king, against 2.6m x 2.8m for the UK double.
Is a UK double Emerald 16500 too big for one person?
Not at all. It's 45cm wider than the UK single at the same length, which gives a solo sleeper generous room to spread out, and space to spare if a pet shares the bed. If your bedroom is on the small side, the UK small double is 15cm narrower and may fit the room better.