Harrison Spinks Bronze 3500 Pocket Ortho Mattress (Firmer Feel)
Mattress
Harrison Spinks Bronze 3500 Pocket Ortho Mattress (Firmer Feel)
Size
Firmness
Firm
Construction
Depth (cm)
27
Layers
5
Layer Details
- British wool. A layer of British wool creates a plush, sumptuous sleeping surface. Wool also regulates temperature naturally, which means you're less likely to wake up clammy.
- Cotton, hemp and flax blend. A blend of cotton, hemp and flax wicks moisture away from your body. In practice, that keeps the mattress feeling fresher for longer.
- Hemp and Ecotex fibres. Hard-wearing hemp and strong Ecotex fibres complete the comfort layers. These add durability, which means the surface should hold its shape over time.
- Micro springs. Layers of 2500 micro springs sit beneath the fillings, adding gentle bounce. They adapt to your body, which means a more responsive feel than fillings alone.
- Pocket springs. The base layer holds 1000 Cortec Quad Revolution pocket springs. Each spring moves independently, which means support where you need it and less disturbance from a restless partner.
Layer details from mattressonline.co.uk product page, September 2026.
- Real width for one sleeper: At 120cm wide, the UK small double is 30cm wider than the UK single, which means a solo adult can starfish without a corner of the mattress going spare.
- Fits compact double bedrooms: It is 15cm narrower than the UK double, often the difference between a door that clears the bed frame and one that doesn't in a box room or loft.
- Firm support across a smaller footprint: The 1000 Cortec Quad Revolution pocket springs give firm, even support edge to edge, useful on a narrower mattress where you sleep closer to the sides.
- Breathable natural fillings: British wool, cotton, hemp and flax wick moisture, which matters in the smaller rooms this size usually goes into, where air circulates less freely.
- Guest-ready for occasional couples: With 2500 micro springs adapting near the surface, two guests can share comfortably for a weekend, even if it is a little snug for every night.
This size suits you if...
You sleep alone and have outgrown a UK single but your room can't give up the floor space a UK double demands, you're furnishing a guest room or holiday let where couples stay occasionally rather than nightly, or you're downsizing and the bed has to suit the new bedroom's dimensions. In each case you also want a firm, traditional spring feel rather than foam.
Consider another size if...
You share the bed every night and want proper space for two, and your room measures at least 2.6m x 2.8m. We'd recommend the UK double instead: it's 15cm wider than the UK small double, the same length.
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Is the Bronze 3500 small double big enough for two adults?
For occasional nights, yes. Across the 120cm width two people can share comfortably for a weekend, and the pocket springs move independently so one restless sleeper disturbs the other less. For nightly couple use it feels snug, and we'd point you to the UK double, which is 15cm wider and the same length.
Will the Bronze 3500 small double fit a standard 4ft frame?
Yes. The UK small double is a standard UK size at 120 x 190cm, or 4ft x 6ft 3in, so 4ft frames, fitted sheets and headboards are straightforward to find. Check your frame's depth allowance too: this mattress is 27cm deep, so a shallow-sided divan or low headboard may sit slightly below the sleep surface.
What room size do I need for a UK small double?
We suggest allowing at least 2.4m x 2.8m. That leaves enough clearance to open the door, walk around the bed and fit a wardrobe or chest of drawers, which is usually the deciding factor in the box rooms and loft conversions this size ends up in. Measure the room, then check the door swing before ordering.
Is a firm mattress a good pick for a small double used solo?
Often, yes. A solo sleeper on a 120cm mattress tends to use the whole surface, and the firm pocket spring base keeps support consistent right across it. One caution: the retailer listing shows this model in soft to medium, medium and firm options despite the firmer badging, so confirm the feel with the retailer before you order.
Should a solo sleeper choose the small double or the UK double?
If your room comfortably exceeds 2.6m x 2.8m and you like maximum sprawl, the UK double gives you 15cm more width at the same length. If space is tighter, the UK small double still offers 30cm more width than a UK single, which is a noticeable upgrade without swallowing the room. Compare prices for both in the retailer table on this page.