Sealy Immerse Hybrid Geltex Double Mattress
The Sealy Immerse Hybrid Geltex is a medium firm hybrid mattress combining a 1400 pocket spring unit with Geltex, a gel-infused foam designed for pressure relief and breathability.
- Geltex & Tencel keep you cooler
- Allergy UK Seal of Approval
- Minimises partner disturbance
£999
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Sealy Immerse Hybrid Geltex Mattress
More available sizes
Mattress details
Mattress
Sealy Immerse Hybrid Geltex Mattress
Size
Firmness
Medium Firm
Construction
Hybrid
Depth (cm)
29
Layers
3
Layer Details
Geltex® Memory Foam
A gel-infused foam that cradles your body for pressure relief while staying breathable, which means you get the contouring of memory foam with less of the heat build-up. It sits at the top, so this is the feel you'll notice first.
Tencel® Fibres
Soft, eco-friendly fibres that give the sleep surface a silky-smooth feel. They're naturally breathable, helping the mattress stay fresh and comfortable through the night.
1400 Pocket Springs
Each spring sits in its own fabric pocket and moves independently, which means support adjusts to your shoulders and hips rather than pushing back as one block. This also cuts down on motion transfer between partners.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- A shared size for typical rooms: At 135 x 190cm, the UK double gives couples a proper shared bed while leaving space for wardrobes and drawers in an average room.
- Motion isolation matters most at this width: With 67.5cm each for two people sharing, the 1400 independent pocket springs help stop a partner's turning from travelling across the mattress to you.
- Cooler sleep at close quarters: Two people in a double generate more warmth than one, so the breathable Geltex foam and Tencel fibres are doing useful work here.
- Bedside tables on both sides: In a room around 3m x 3m, this size usually leaves enough clearance for a table each side, which a UK king often doesn't.
- Easy to dress: Standard double sheets and a 200 x 200cm double duvet fit, and both are stocked everywhere at every price point.
This size suits you if...
You share the bed every night and want a size that fits a typical UK bedroom rather than filling it, or you sleep alone and like room to stretch out, perhaps with a dog or cat claiming a corner. It also suits a guest room that hosts visiting couples, since the medium firm feel works for most back and combination sleepers.
Consider another size if...
You and your partner both sleep hot or move around a lot, since 67.5cm each can feel snug. If your room allows at least 2.7m x 2.9m, we'd recommend the UK king instead: it is 15cm wider and 10cm longer.
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FAQ's
What are the dimensions of the Sealy Immerse Hybrid Geltex in a UK double?
This size measures 135 x 190cm, or 4ft 6in x 6ft 3in. It is 29cm deep, so factor that into fitted sheets, and check the mattress will make it up any turning stairs or a tight landing before delivery day.
How much space does each person get on the Sealy Immerse Hybrid Geltex double?
Two people sharing get 67.5cm each. That is snug rather than generous, although the 1400 pocket springs move independently, which means a restless partner disturbs you less than the width alone might suggest. If you both spread out in your sleep, consider the UK king, which is 15cm wider.
What room size do I need for the Sealy Immerse Hybrid Geltex in a double?
We suggest at least 2.6m x 2.8m, with around 3m x 3m the comfortable norm. That larger figure typically leaves room for bedside tables on both sides plus a wardrobe, which is why the UK double remains the default choice for average British bedrooms.
Is the double big enough for a couple who both run warm?
Sharing a double puts two warm bodies close together, so heat matters more here than in a larger size. The Geltex foam and Tencel fibres are designed to draw warmth away rather than trap it, which helps. Very hot sleepers with the room space may still prefer the wider UK king.
Where can I compare prices for the Sealy Immerse Hybrid Geltex UK double?
Use the price table on this page. The figures shown are live and updated as retailers change them, so you are always looking at current pricing rather than a snapshot. Retailer line-ups shift over time too, so it is worth checking back before you commit.