Flaxby Platinum Eclipse Super King Mattress
The Flaxby Platinum Eclipse is a firm, handmade natural mattress with 13,440 calico pocket springs and comfort layers of wool, cotton, mohair, silk, cashmere and alpaca.
- Firm support for back & front sleepers
- Natural fibres help regulate heat
- Minimises partner disturbance
£5,599
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Flaxby Platinum Eclipse Mattress
More available sizes
Mattress details
Mattress
Flaxby Platinum Eclipse Mattress
Size
Firmness
Firm
Construction
Foam
Pocket Spring
Wool
Memory Foam
Natural
Depth (cm)
35
Layers
4
Layer Details
Comfort layers
Naturally soft layers of wool, cotton, mohair, silk, cashmere and alpaca sit at the top. These fibres breathe well and wick moisture, which means a surface that feels soft against you without trapping heat.
Temperature-regulating layers
Beneath the comfort fillings sit naturally temperature-regulating layers of hemp and flax. These help keep the mattress closer to a steady temperature through the night, a genuine plus if you run hot.
Pocket springs
The core is over 13,000 handsewn calico pocket springs. Each spring moves independently, which means support that follows your shape and less disturbance when a partner shifts position.
Micro springs
Two layers of high density micro springs add extra contouring support above the main unit. In practice this softens the transition between the firm spring core and the natural fillings, so the surface adapts more precisely to shoulders and hips.
Layer details from featherandblack.com product page, September 2026.
Key benefits
- Real distance from a restless partner: With 90cm each, the 13,440 calico pocket springs barely need to work at motion isolation, because most movement happens too far away to feel.
- Room for the whole household: Children or a large dog joining you at 3am still leaves adults with usable space, which smaller sizes simply cannot offer.
- A firm surface across a full 6ft: The consistent, firm spring support holds its feel edge to edge, so neither sleeper drifts into a dip in the middle.
- Natural fillings scaled up: Wool, cashmere, hemp and flax breathe across the whole 180cm width, useful when two warm bodies share one bed all night.
- Proportion for larger rooms: In a big master bedroom or period property, a UK super king fills the space in a way a UK king can look lost in.
This size suits you if...
You share the bed every night and want enough width that neither of you compromises, your children or pets treat your bed as their own, or your master bedroom is large enough that a UK king would look undersized. It also suits you if your partner is genuinely restless, since at this width distance does more than any comfort layer could.
Consider another size if...
Your bedroom falls short of the 3m x 2.9m we suggest as a minimum, or you sleep alone. The UK king would suit you better: it's the same length, 30cm narrower, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
Is the Flaxby Platinum Eclipse in a UK super king good for couples?
Yes, and arguably this size makes the strongest case for sharing. You get 90cm each for two people, so the mattress's firm, independent pocket spring support works with real physical distance between you. If one of you turns often through the night, the width matters more than any filling. Both sleepers should be happy with a firm feel, though.
How much space does each person get on a super king Platinum Eclipse?
Two people sharing get 90cm each. That's enough to stretch out, change position or sleep with an arm flung wide without touching your partner. It also means a child who climbs in during the night can usually be absorbed without anyone ending up on the edge, which is where this size proves its value for families.
How does the UK super king compare with the UK king for this mattress?
The UK super king is 30cm wider than the UK king, and the two are the same length. That extra width is the whole argument: it's the difference between sharing comfortably and sharing carefully. For rooms, we suggest at least 3m x 2.9m for the UK super king and at least 2.7m x 2.9m for the UK king.
Can the Flaxby Platinum Eclipse super king be carried upstairs easily?
Treat this as a two-person job at minimum. It's 6ft x 6ft 6in, 35cm deep and filled with natural fibres and handsewn springs, so it won't bend or compress the way a rolled foam mattress does. Measure your stairwell, any landing turns and the bedroom door swing before ordering, because at this size a tight corner can be a dealbreaker.
Where can I buy the Platinum Eclipse in a super king?
Compare the retailers listed on this page. The prices shown here are live and updated as retailers change them, so checking the table is more reliable than any figure we could print. Given this mattress sits at the luxury end of the market, it's a size and model where shopping around genuinely pays.