Harrison Spinks Byron Mattress
Mattress
Harrison Spinks Byron Mattress
Size
Firmness
Construction
Depth (cm)
29
Layers
4
Layer Details
- Top surface. Generously layered with 100% natural cashmere, mohair, cotton, hemp, flax and British wool. This is the winter side, where insulating wool with silk absorbs moisture and helps regulate temperature, which means fewer clammy nights in colder months.
- Fillings. Soft cashmere, sourced as a byproduct from the fashion industry, brings insulation and a supremely gentle surface feel. It sits alongside traceable British sheep's wool from the British Wool partnership.
- Springs. 13,060 responsive springs across seven layers of high-density micro and Cortec pocket springs, which means very precise, localised support. The Cortec system is glueless and 100% recyclable.
- Reverse surface. A breathable cotton side designed for summer use. Flip the mattress with the seasons to get the right sleeping temperature year round.
Layer details from featherandblack.com product page, September 2026.
- Distance beats any comfort layer: With 90cm each for two people sharing, a fidgeting partner is simply too far away to feel, before the springs even do their work.
- Springs and space working together: The 13,060 micro and Cortec pocket springs localise movement, so on a surface this wide one sleeper turning barely registers on the other side.
- Room for the whole household: When a child pads in at 3am, or the dog treats the bed as routine, 180cm of width absorbs an extra body without anyone losing their share.
- A firm bed that fills a big room: In a large master or period bedroom where a UK king can look undersized, the super king sits in proportion and keeps the Byron's firm, supportive feel edge to edge.
- Natural fillings at full scale: Cashmere, wool, silk and cotton across the full 180 x 200cm surface, with the wool-rich winter side helping both sleepers stay a comfortable temperature.
This size suits you if...
You share the bed every night and want the most sleeping space a standard UK size offers, your partner is restless enough that a UK king still feels crowded, or children and pets regularly join you and 150cm of width no longer stretches to everyone. Your bedroom should measure at least 3m x 2.9m for this size to sit comfortably.
Consider another size if...
Your bedroom falls short of the 3m x 2.9m we suggest for a UK super king, or you'd struggle to flip a mattress this large seasonally. We'd recommend the UK king instead: it's 30cm narrower, the same length, and needs at least 2.7m x 2.9m.
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Is the Harrison Spinks Byron hard to flip in a UK super king?
It takes two people. The Byron is a 29cm deep, densely filled natural mattress that needs flipping between its winter and summer sides, and at 180 x 200cm the super king is the largest size most couples will manage. If seasonal flipping worries you, a smaller size of the Byron is easier to handle.
How much space does each person get on a super king Byron?
90cm each for two people sharing, the same width as a UK single apiece. Combined with the Byron's 13,060 pocket springs, which respond locally rather than transferring movement across the bed, that distance means a restless partner turning over is very unlikely to wake you.
Will a super king Byron work if children or pets join us at night?
This is the size for it. At 180cm wide there's room for a wandering child or a large dog without either adult being pushed to the edge, and the firm surface keeps its support consistent right across the bed rather than sagging where the extra weight lands.
Should I get the Byron in a UK king or a UK super king?
The UK super king is 30cm wider than the UK king and the same length. If your partner is restless, or the bed is regularly shared with children or pets, that extra 30cm makes a real difference. The deciding factor is usually the room: allow at least 3m x 2.9m for the super king, or 2.7m x 2.9m for the UK king.
Where can I buy the Byron super king at the best price?
Compare the retailers listed on this page. The prices shown here are updated as retailers change them, so what you see reflects the current cost of the Byron in a UK super king rather than a figure that's gone stale. Stock and pricing can differ from the smaller sizes.