Sealy Advantage Sapphire Geltex Pillow Top Double Mattress
The Sealy Advantage Sapphire Geltex Pillow Top Mattress combines a plush pillow top with a gel-infused Geltex comfort layer, which means a cushioned surface that eases pressure where you feel it most.
- Eases pressure where you feel it
- Support that responds as you move
- Reinforced edges for steady sides
£599
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Sealy Advantage Sapphire Geltex Pillow Top Mattress
More available sizes
Mattress details
Mattress
Sealy Advantage Sapphire Geltex Pillow Top Mattress
Size
Firmness
Medium
Construction
Gel
Memory Foam
Pocket Spring
Depth (cm)
28
Layers
3
Layer Details
Pillowtop
A plush pillow top that adds an extra layer of cushioning, which means a softer-feeling surface than the medium rating alone suggests.
Geltex comfort layer
A cushioned, gel-infused Geltex layer that relieves pressure on the parts of the body that feel it most, so your hips and shoulders get some extra give.
PostureTech CS spring system
Pocket springs that respond to shifts in body weight to give localised support, with Edge Guard foam strips inside the spring unit. You get support that follows your movements, plus steadier edges.
Layer details from mattressnextday.co.uk product page, October 2026.
Key benefits
- Room to share without filling the room: A UK double needs at least 2.6m x 2.8m by our guidance, which means many second bedrooms and first flats can still take a wardrobe and drawers alongside it.
- Steadier sides for a shared bed: Each sleeper gets 67.5cm on a UK double, so you spend more time near the edge, and the Edge Guard foam strips inside the spring unit should make that edge feel more dependable.
- Support that responds to each of you: The PostureTech CS springs respond to shifts in body weight to give localised support, which means two people of different builds each get support where they press down.
- Cushioning where you lie: The pillow top and gel-infused Geltex layer give your hips and shoulders some extra give, a comfort many couples value on a medium-rated mattress.
- Bedding is easy to find: Double sheets and a 200 x 200cm double duvet fit, and they're sold almost everywhere, which helps if you're furnishing a whole home at once.
This size suits you if...
You share the bed with a partner and your bedroom is around 3m x 3m or a little smaller, or you want bedside tables on both sides without squeezing past them, or you're kitting out a guest room for visiting couples.
Consider another size if...
Either of you sprawls across the bed, or you're both tall and want extra length. We'd recommend the UK king instead: it gives 75cm each and is 10cm longer, and we suggest at least 2.7m x 2.9m for it.
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FAQ's
Is the Sealy Advantage Sapphire Geltex Pillow Top double big enough for two people?
For most couples, yes. A UK double gives 67.5cm each, which suits two average-sized sleepers who don't mind being fairly close. If one of you moves a lot through the night, that space can feel snug. The Edge Guard foam strips help here, because you can use the full width with the sides feeling steadier.
What size bedroom do I need for a UK double Sealy Sapphire pillow top?
We suggest at least 2.6m x 2.8m for a UK double, with around 3m x 3m the comfortable norm. At the smaller end, think about whether you still want bedside tables on both sides and a wardrobe door that opens fully. Measure with those in mind rather than the mattress alone.
Should I get the Sealy Sapphire Geltex in a UK double or a UK king?
Choose by room and by how much space you each need. The UK king is 15cm wider and 10cm longer, giving 7.5cm more each, but we suggest at least 2.7m x 2.9m for it. If your bedroom is tighter than that, the UK double keeps the room usable.
What bedding fits the Sealy Advantage Sapphire UK double?
Standard double sheets fit the 135 x 190cm surface, and a 200 x 200cm double duvet suits it well. The mattress is 28cm deep and has a pillow top, so look for fitted sheets with deep pockets. Sheets made for slimmer mattresses can pull off the corners.
Will a UK double Sealy Sapphire mattress fit up narrow stairs?
A UK double is 135 x 190cm and 28cm deep, so check the narrowest part of your stairway and any turns against those figures. Turning stairs in older terraces and tight landings in new builds are the usual sticking points. Measure the route first, then compare the retailers listed on this page.