Temperature
Foam holds heat.
Springs do not.
A foam mattress is a block, and heat has nowhere to go in a block. Ours is 3 things working together: Coolcell at the surface, Coolweave over the top, and 20,000 pockets of air in Sevencore beneath. Built to move heat, not hold it.
![[Cover] cover, close](http://onnilondon.co.uk/cdn/shop/t/5/assets/coolknit-macro.webp?v=112201380616359129721788369559)
3 things, in order
3 parts.
One system.
Coolcell takes the heat off you
1 centimetre of gel, 1 centimetre from your skin. Not buried in the middle of a foam block where it warms up and stays warm, but at the surface, where the heat actually is.
Coolweave lets it go
400gsm, 4 times the weight of a standard cover, and the most effective cooling material on the market. Knitted open, so everything Coolcell pulls off you walks straight out instead of sitting there.
Sevencore gives it somewhere to be
20 centimetres of pocket springs is mostly air. A foam block holds heat because heat has nowhere to go in a block. This is 2,000 springs and the space between them.
Onni London+ Coolcell
Gel in the middle
does nothing.
Every mattress claims cooling gel. Most of them bury it in the middle of a foam block, where it absorbs heat for an hour and then holds it against you all night, because there is nowhere for that heat to leave.
Coolcell sits 1 centimetre from the surface, directly beneath Coolweave. It takes the heat off your skin where you can actually feel it, and the cover carries it out of the bed. Same material everyone else uses, put somewhere it can work, and the difference is the whole night.
If it is still too warm
Tell us.
Heat is usually a comfort layer question. A firmer face keeps you higher on the surface, which is cooler. Turn it over first. If that is not enough, tell us, and we build a new layer to what you describe. For a year, with our compliments.
You do not choose the feel. You discover it. Temperature is part of feel.
Reserve yours
Choose your size.
Every size is the same build. 35 centimetres, seven-zone core, removable comfort layer. You do not choose a firmness.
It arrives medium firm with a flippable comfort layer.
Optional. It reaches the person who makes your mattress.
A year to tell us how it should feel. We remake the comfort layer to that, with our compliments, as often as it takes.
Collected from your home and refunded in full. Emperor is made to order and excluded.
The part that carries you is guaranteed for a quarter of a century.