Luna 4000 Plush Gel Memory Pocket Hybrid Small Double Mattress
The Luna 4000 Plush Gel Memory Pocket Hybrid is a 25cm deep hybrid mattress that pairs a full pocket spring system with gel-infused memory foam, which means you get the contouring hug of foam without losing the responsive support of springs.
- Softer feel for side sleepers
- Mini springs fine-tune pressure relief
- Open-cell foam lets heat escape
£324
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Luna 4000 Plush Gel Memory Pocket Hybrid Mattress
More available sizes
Mattress details
Mattress
Luna 4000 Plush Gel Memory Pocket Hybrid Mattress
Size
Firmness
Medium Soft
Construction
Foam
Pocket Spring
Hybrid
Rolled
Memory Foam
Depth (cm)
25
Layers
5
Layer Details
Knitted cover
A soft knitted top designed to enhance airflow and breathability. It adds a cosy, slightly plush first impression when you lie down.
Luna Fusion Cool Memory Foam
A 2cm layer of open cell memory foam, which means it lets heat escape more readily than standard memory foam while still moulding to your shape. It provides that gentle, cradled feel memory foam is known for.
Reflex Foam
Two 3cm layers of supportive foam that mould to your body and help keep your spine aligned. This is the transition zone between the soft top and the springs below.
Mini Pocket Springs
Small, individually cased springs that add a layer of fine-tuned pressure relief and reduce motion transfer, which means less disturbance when a partner shifts in the night.
Luna Pocket Springs
Full-size steel springs sewn into individual fabric pockets, each responding independently to your weight and movement. This is the mattress's main support system, keeping your body properly aligned.
Layer details from mattressonline.co.uk product page, September 2026.
Key benefits
- Room to spread out alone: At 120cm wide, the UK small double is 30cm wider than the UK single, which means a solo sleeper can roll over without meeting the edge.
- Fits rooms a double cannot: It is 15cm narrower than the UK double, often the difference between a door that clears and one that scrapes in a box room or studio.
- A softer feel suits solo sleepers: The soft to medium gel memory foam top lets shoulders and hips settle in, which works well when there is no partner to compromise with.
- Handles the occasional shared night: The mini pocket spring layer reduces motion transfer, so a guest room small double copes with a visiting couple for a weekend without much disturbance.
- Standard 4ft bedding and frames: The small double is a standard UK size, so fitted sheets and frames are easy to find, and a normal double duvet drapes generously over it.
This size suits you if...
You're a solo adult who has outgrown a single and wants proper stretching room, your bedroom, loft conversion or studio can't take the width of a full double, or you're furnishing a guest room where couples stay occasionally rather than nightly. Allow at least 2.4m x 2.8m of floor space and the UK small double sits comfortably.
Consider another size if...
You share the bed every night, because 120cm is snug for two on a regular basis. We'd recommend the UK double instead, which is 15cm wider; allow at least 2.6m x 2.8m for it.
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FAQ's
Is a small double big enough for the Luna 4000 to work for a couple?
For occasional nights, yes. The mini pocket springs limit motion transfer, so a visiting couple in a guest room will manage fine. For every night, 120cm across is tight for two adults, and the soft to medium feel means two bodies sink towards the middle. Nightly sharers would be happier on the UK double.
What room size do I need for a UK small double mattress?
We suggest allowing at least 2.4m x 2.8m. That leaves enough space to walk round the bed and open drawers, which matters in exactly the rooms this size is bought for: box rooms, lofts and compact second bedrooms. Measure with the door swing in mind, as width is usually what decides it.
How much bigger is the Luna 4000 small double than the single?
The UK small double is 30cm wider than the UK single, and the two are the same length at 190cm. That extra width is the whole point: a teenager or adult who has outgrown a single gets real turning room, while the room only needs to find a little more floor space.
Does the soft feel of the Luna 4000 suit a solo sleeper on a small double?
Generally, yes. Sleeping alone, you can pick the feel that suits you rather than splitting the difference with a partner, and the soft to medium surface favours side sleepers and lighter bodies. Heavier back or stomach sleepers may sink too far regardless of size, so the small double doesn't change that caution.
What bedding fits the Luna 4000 in a small double?
You need small double (4ft) fitted sheets, which are widely stocked as it's a standard UK size. A standard double duvet works well on top and drapes a little further down each side than it would on a UK double, which many solo sleepers rather like.