Spring King Ruby Ortho Extra Firm Double Mattress
The Spring King Ruby Ortho Extra Firm is an orthopaedic open coil mattress at the firmest end of the scale.
- Extra-firm for back & front sleepers
- Even support with less sinking
- Breathable cover helps you stay cool
£259
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Spring King Ruby Ortho Extra Firm Mattress
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Mattress details
Mattress
Spring King Ruby Ortho Extra Firm Mattress
Size
Firmness
Extra Firm
Construction
Orthopaedic
Open Coil Spring
Depth (cm)
27
Layers
3
Layer Details
Cover
A breathable Belgian damask fabric cover. The breathability helps air move away from your body, which means you are less likely to overheat.
Comfort Fillings
Soft white fibre fillings made from 100% polyester. These add a little softness over the springs, though the overall feel remains extra firm.
Support System
A traditional open coil unit built from one continuous high tensile spring formed into a lattice. This spreads support evenly across the mattress, which means a stable, uniformly firm surface underneath you.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Fits a typical shared bedroom: At 135 x 190cm, or 4ft 6in x 6ft 3in, it sits comfortably in rooms where a UK king would crowd out the wardrobe and drawers.
- Even firmness across the full width: The continuous coil lattice spreads support from edge to edge, which means neither of you drifts towards a softer middle when you both lie on your back.
- Space to walk around: We suggest at least 2.6m x 2.8m, although around 3m x 3m gives you a bedside table each and room to get in without shuffling sideways.
- A sensible guest room choice: Visiting couples who prefer a hard bed get a proper shared size, and double sheets and a 200 x 200cm duvet are easy to find.
- Cooler with two in the bed: Two bodies make more warmth, and the breathable Belgian damask cover lets air move away from you, so the shared surface is less likely to feel stuffy.
This size suits you if...
You share a bed with someone who also likes an extra firm feel, and you want to keep enough floor for bedside tables and a wardrobe. It also fits if you are furnishing a guest room for visiting couples who mostly sleep on their back or front.
Consider another size if...
Your partner is a restless sleeper, or you already feel short of space at 67.5cm each. We'd recommend the UK king instead, which gives 75cm each; allow at least 2.7m x 2.9m.
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FAQ's
Will I feel my partner move on a Ruby Ortho UK double?
Probably, yes. Open coil units tend to move as one, and on a UK double you each have 67.5cm, so you are lying fairly close together. The UK king gives 75cm each, which helps a little with the movement you notice, although it will not stop the springs moving together.
Is the Ruby Ortho UK double long enough for a tall couple?
The UK double is 190cm long, the same as the UK single and UK small double. If either of you finds your feet reaching the end, the UK king is 10cm longer, as well as 15cm wider. We suggest at least 2.7m x 2.9m for the UK king, so check your room first.
Can a Ruby Ortho UK double fit in a small bedroom?
We suggest at least 2.6m x 2.8m for a UK double. If your room falls short of that, the UK small double is 15cm narrower and the same length, and we suggest at least 2.4m x 2.8m for it. That is a closer fit for two, but it can save you from squeezing past the furniture.
Ruby Ortho UK double or UK king for two back sleepers?
If you both like firm support and your room allows at least 2.7m x 2.9m, the UK king gives 75cm each and 10cm more length. The UK double gives 7.5cm less each, which suits couples who sleep fairly still and would rather keep floor space for bedside tables on both sides.
Is a Ruby Ortho UK double worth it for one person with a dog?
It can be. A solo sleeper on a UK double has room to stretch while a dog or cat claims a corner, and the extra firm surface stays flat even where your pet lies. If the pet sleeps elsewhere, the UK single is 45cm narrower and needs at least 2.1m x 2.8m.