Harrison Spinks Ruby 12500 Pocket King Size Mattress (Firmer Feel)
The Harrison Spinks Ruby 12500 Pocket Mattress (Firmer Feel) is a pocket spring mattress with a firm feel.
- Designed firm from the start
- Localised support at hips & shoulders
- From a long-established British maker
£1,899
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Harrison Spinks Ruby 12500 Pocket Mattress (Firmer Feel)
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Mattress details
Mattress
Harrison Spinks Ruby 12500 Pocket Mattress (Firmer Feel)
Size
Firmness
Firm
Construction
Pocket Spring
Wool
Natural
Depth (cm)
Layers
5
Layer Details
Mini pocket springs
Small, individually cased springs sit in the comfort layer and add cushioning while cutting down motion transfer. In practice, you get a little give on top of the firm feel, and less disturbance when a partner moves.
Wool
Wool comfort filling, described as a natural insulator with temperature-regulating properties. It helps keep you from getting too warm or too cool as the night goes on.
Cotton
Natural cotton fibres create a fresh sleeping environment and wick away moisture. That should help the surface feel drier and fresher, especially if you tend to sleep warm.
Hemp
Hemp is an eco-friendly fibre that is naturally breathable and durable. It lets air move through the filling and should help the mattress keep its feel over time.
Flax
Flax fibres are durable and breathable, and are described as having anti-bacterial properties. This is a hard-wearing natural layer that adds to the airy feel of the fillings above it.
Layer details from mattressonline.co.uk and simplybedssussex.co.uk product pages, October 2026.
Key benefits
- 75cm each for two people sharing: You each get 75cm of width, which means you can settle into your own sleeping position without negotiating for space every night.
- Pocket springs limit partner disturbance: Because each spring compresses independently, one of you getting up for an early start is far less likely to wake the other.
- 200cm of length for taller sleepers: The UK king is 10cm longer than the UK Double, so a partner approaching six foot stops sleeping diagonally or hanging feet off the end.
- A firm surface that stays consistent across the width: The firmer feel is built in across the whole mattress, so you get the same support at the edge as in the middle of your side.
- Fits most master bedrooms: We suggest allowing at least 2.7m x 2.9m, which most UK master bedrooms manage without giving up bedside tables on both sides.
This size suits you if...
You share the bed every night and want genuinely more room than a UK double offers, or one of you keeps different hours and needs to get up without disturbing the other. It also suits couples where one partner is tall, since the 200cm length removes the cramped feel of a 190cm bed. If a firm pocket spring feel is what your body needs, this is the size most couples should be pricing up.
Consider another size if...
You sleep alone, or your bedroom falls short of the 2.7m x 2.9m we suggest for a UK king. In that case we'd recommend the UK double instead, allowing at least 2.6m x 2.8m for it.
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FAQ's
Is a UK king Harrison Spinks Ruby 12500 big enough for a couple?
Yes, comfortably for most. At 150 x 200cm you get 75cm each for two people sharing, and the pocket spring construction means movement on one side barely carries to the other. If one of you is restless or you share with a pet who claims a corner, the UK super king is 30cm wider still.
Will the UK king suit a partner over six foot?
The UK king is 200cm long, 10cm longer than the UK Double, which is usually the difference between feet reaching the end and feet hanging over it. Anyone up to around 6ft 3in should find the length comfortable; taller than that, the UK super king is the same length, so sizing up adds width only.
What room size do I need for the Ruby 12500 in a UK king?
We suggest allowing at least 2.7m x 2.9m, with more feeling noticeably more comfortable once wardrobes and drawers are in place. New build master bedrooms often look bigger empty than they are furnished, so measure with your existing furniture in mind before committing to this size.
Does the firm feel change in the king size?
No. Firmness comes from the construction, so the Firmer Feel is the same across every size of the Ruby 12500. What changes in the UK king is the space: with 75cm each for two people sharing, neither of you ends up pressed against the other, which matters more on a firm surface where you sink in less.
Should I choose the UK king or the UK super king in this mattress?
The UK king is 30cm narrower than the UK Super King, and the two are the same length, so the decision is purely about width and room size. We suggest at least 3m x 2.9m for the UK Super King. If your room clears that and you value maximum personal space, size up; otherwise the UK king serves most couples well.