Luna 4000 Support Gel Memory Pocket Hybrid Mattress
Mattress
Luna 4000 Support Gel Memory Pocket Hybrid Mattress
Size
Firmness
Medium Firm
Construction
Depth (cm)
25
Layers
4
Layer Details
- Luna Fusion Cool Memory Foam. A 2cm layer of memory foam that adapts around your body, which means gentle pressure relief where you need it. Its breathable, open cell structure lets air move through, giving a cooler, fresher feel than standard memory foam.
- Reflex Foam. Two 3cm layers of Reflex foam add cushioning for extra comfort, which means a slightly softer landing before you reach the springs. They mould to your body and help keep your spine aligned.
- Mini Pocket Springs. A layer of 2,000 mini springs gives a bouncy, comforting feel, so the mattress responds quickly when you change position. Their small size creates pockets of airflow and helps reduce motion transfer between partners.
- Luna Pocket Springs. A core of 2,000 Luna Pocket springs, each encased in its own fabric pocket. They respond individually to changes in weight and movement, which means support is distributed exactly where your body needs it.
Layer details from mattressonline.co.uk product page, September 2026.
- Room to sprawl alone: At 30cm wider than the UK single, this size lets one person change position freely across those 4,000 individually responding springs.
- Fits a compact bedroom: It is 15cm narrower than the UK double, which can be the difference between a door that clears and one that does not.
- Medium firm support at any position: The pocket spring core responds to weight wherever you lie, so a solo sleeper who drifts across the full 120cm width stays supported.
- Cooler for a smaller room: The open cell gel memory foam and airflow through the mini springs help in box rooms and lofts, which often run warmer.
- Handles the occasional guest couple: Two people can share for short stays, and the pocket springs limit motion transfer even at this narrower width.
This size suits you if...
You sleep alone and have outgrown a UK single but your room cannot spare the floor space a full double demands, you're furnishing a guest room or holiday let where couples stay occasionally rather than nightly, or you're downsizing and the bed has to fit the new bedroom rather than the old one.
Consider another size if...
You share the bed every night, as 120cm is a squeeze for two long term. We'd recommend the UK double instead, which is 15cm wider and the same length; allow at least 2.6m x 2.8m for it.
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Is a small double big enough for the Luna 4000's spring system to matter?
Yes. The 2,000 mini springs and 2,000 pocket springs run across the full 120 x 190cm surface, so a solo sleeper who moves around at night gets consistent support edge to edge, rather than a sweet spot in the middle. The medium firm feel is the same as the larger sizes.
Can a couple sleep on the Luna 4000 in a UK small double?
For occasional nights, yes. The pocket springs respond to each person individually, which helps with fidgeting, and the mattress supports two adults comfortably. For every night, though, 120cm is tight for two, and we'd suggest the UK double or UK king of this mattress instead.
What room size do I need for the Luna 4000 small double?
We suggest at least 2.4m x 2.8m, which is our own guidance rather than Luna's. That allows walking space around the 120 x 190cm mattress. If your room is closer to 2.6m x 2.8m, the UK double becomes an option; below our minimum, the UK single may be the wiser fit.
Is the Luna 4000 small double good for a teenager?
It suits a teenager who has outgrown a single but whose room can't lose much floor space, since it adds 30cm of width without any extra length. The medium firm feel offers proper support for a growing sleeper, though anyone wanting a soft, sink-in surface may find it firmer than expected.
How much smaller is the small double than the king in this mattress?
The UK small double is 30cm narrower and 10cm shorter than the UK king. That length difference matters for taller sleepers: at 190cm long, anyone around six foot or over will feel the limit. If your room allows at least 2.7m x 2.9m, the UK king removes that concern.