Harrison Spinks Knaresborough 3750 Pocket Ortho Mattress
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Mattress
Harrison Spinks Knaresborough 3750 Pocket Ortho Mattress
Size
Firmness
Firm
Construction
Pocket Spring
Orthopaedic
Depth (cm)
24
Layers
2
Layer Details
Comfort fillings
Wool, cotton, hemp and soft white fibres, finished with tufted layers, give natural insulation and help regulate temperature. For you, that means a breathable, foam-free top that should feel less clammy than a dense synthetic surface.
Support system
3750 individual pocket springs sit in cloth pockets, so each spring works on its own. This gives more tailored support to each part of your body, with the firm, no-sink feel the mattress is known for.
Layer details from mattressonline.co.uk product page, October 2026.
- Springs that keep the peace: Pocket springs compress independently, which means an early alarm and a quiet exit on one side of the 150cm width is far less likely to wake the other.
- 75cm each, every night: Two sharers get 75cm apiece, which means you can lie flat on your back on a firm surface without negotiating elbow room.
- Extra length for taller sleepers: At 200cm, the UK king is 10cm longer than a UK double, a genuine relief if one of you is approaching six foot.
- Firm support across the full width: The ortho-firm feel keeps your spine in a neutral line whether you sleep centrally or, more realistically, pushed to your own half.
- Room for the dog, within reason: If a dog on the bed is part of the routine, the extra 15cm over a UK double absorbs some of that lost space.
This size suits you if...
You share the bed every night and have outgrown a UK double, especially if you both like a firm, no-sink surface and want to feel less of each other's movement. It also suits couples on different schedules, where one of you gets up hours earlier, and anyone tall enough to appreciate the 200cm length. Your room should measure at least 2.7m x 2.9m.
Consider another size if...
Your bedroom falls short of the 2.7m x 2.9m we suggest, which is common in newer builds once wardrobes go in. We'd recommend the UK double instead; allow at least 2.6m x 2.8m for that size.
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Is a UK king big enough for a couple on a firm mattress?
Yes, comfortably for most. You get 75cm each for two people sharing, and because this is a firm mattress you tend to stay on your own half rather than rolling towards the middle. If one of you sprawls, or a dog routinely claims a corner, the UK super king adds another 30cm of width.
Will I feel my partner getting up early in a king size Knaresborough 3750?
Less than you would on a smaller bed. The pocket springs move independently, so movement on one side transfers weakly to the other, and the 150cm width puts more distance between you than a UK double. Across a firm build like this, an early riser sliding out is unlikely to disturb a settled sleeper.
Is the UK king Knaresborough 3750 long enough for someone over six foot?
At 200cm, or 6ft 6in, it gives a tall sleeper 10cm more length than a UK double, which is usually the difference between feet on the mattress and feet hanging off the end. The UK super king is the same length, so sizing up buys width, never extra length.
Will a king size fit in a new build master bedroom?
Often, but measure first. We suggest at least 2.7m x 2.9m for a UK king, and new build masters can feel smaller than the floor plan suggests once fitted wardrobes and bedside tables are in. If yours falls short, the UK double needs at least 2.6m x 2.8m and gives up only 15cm of width.
Where can I buy the Knaresborough 3750 in a UK king?
Availability is limited for this range, so compare the retailers listed on this page; the prices shown here update as retailers change them. If your heart is set on the UK king specifically, it's sensible to check stock before planning delivery around a bed frame purchase.