Sleepeezee ActivFlex Response 3600 Pocket Pillow Top Single Mattress
The Sleepeezee ActivFlex Response 3600 Pocket Pillow Top Mattress combines two Staycool Gel foam layers with three tiers of pocket springs, which means a soft, cushioned surface that stays cool with support underneath.
- Cushioned pillow top comfort
- Gel layers keep you cooler
- 10-year guarantee
£899
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Sleepeezee ActivFlex Response 3600 Pocket Pillow Top Mattress
More available sizes
Mattress details
Mattress
Sleepeezee ActivFlex Response 3600 Pocket Pillow Top Mattress
Size
Firmness
Medium Soft
Construction
Foam
Gel
Pocket Spring
Depth (cm)
33
Layers
9
Layer Details
Soft knitted cover
The knitted pillow top cover that you sleep on. It gives the mattress a soft, quilted-feel finish.
Soft polyester comfort layer
A soft polyester fibre layer under the cover. It adds surface cushioning, so the mattress feels gentle as you lie down.
Staycool Gel
Two dedicated layers of Staycool Gel foam, which Sleepeezee describes as pressure-sensitive and cooling. They ease pressure and help the surface stay cooler.
ActivFlex spring foam
A profiled foam that combines the adaptive benefits of foam with the responsiveness of springs. You get contouring without feeling stuck in the mattress.
1000 mini comfort springs
A top layer of mini pocket springs nestled within the pillow top. They add a responsive, close-fitting layer of comfort near the surface.
1400 mini comfort springs
A middle layer of mini pocket springs that adds responsiveness. It helps the mattress react as you move.
1200 traditional pocketed springs
The core layer of main pocket springs that provides the foundation and support. This is what holds your weight steady beneath the softer layers.
Fully encapsulated spring unit
A high-density foam border surrounds the spring unit to give edge-to-edge support. It makes the sides firmer to sit on and gives you more usable sleeping space.
Foundation support pad
A support pad that forms the foundation for the layers above. It sits at the base and supports the springs.
Layer details from sleepeezee.com product page, October 2026.
Key benefits
- Leaves room for everything else: We suggest allowing at least 2.1m x 2.8m of floor space, which means a desk, wardrobe or toy storage can usually sit alongside the bed.
- Cushioning for lighter bodies: The medium soft rating and pillow top give a gentle surface, which means children, teens and lighter adults get plenty of give without needing a bigger bed.
- Steadier edges on a narrow bed: A high-density foam border surrounds the springs, which matters on a 90cm width where you spend more of the night close to the side.
- Easy bedding for guest rooms: It takes standard single sheets and a single duvet (135 x 200cm), so making up a spare bed for visitors is straightforward.
- No flipping for teenagers or guests: It's single-sided, so nobody has to turn it, although that also means you can't flip it to spread the wear.
This size suits you if...
You sleep alone and like a soft, cushioned surface, you're furnishing a child's or teenager's room with a divan or low frame, or you want a comfortable guest bed for a spare room that also works as a study.
Consider another size if...
You share the bed, or you want space to spread out on a soft surface. We'd recommend the UK small double instead: it's 30cm wider at the same length, and we suggest at least 2.4m x 2.8m.
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FAQ's
Will the Sleepeezee ActivFlex Response 3600 Pillow Top UK single fit a bunk bed?
Possibly not. The mattress is 33cm deep, and bunk, cabin and mid-sleeper frames normally set a maximum mattress depth so the safety rail still sits high enough above the sleeper. Check the frame maker's guidance before you order; if the limit is lower than 33cm, this mattress isn't the right choice for that bed.
What size bedroom do I need for a UK single pillow top mattress?
We suggest at least 2.1m x 2.8m for a UK single. That leaves enough floor for a walkway and some furniture, which is useful in a child's room competing for space with a desk and storage, or a box room that doubles as a home office.
Is a UK single ActivFlex Response pillow top a good choice for a child?
For most younger children, yes. Sleepeezee rates it medium soft, and lighter bodies suit that level of cushioning well. As a teenager grows heavier they may want more support than a medium soft rating suggests, so keep that in mind if you're buying for the long term.
What bedding fits a 3ft single mattress that is 33cm deep?
Standard single sheets and a single duvet (135 x 200cm) fit the 90 x 190cm surface. The depth is the catch: at 33cm, choose fitted sheets with deep pockets, because shallow ones tend to pull off the corners of a pillow top mattress.
Should I buy a UK single or UK small double for a teenager's room?
A UK single suits a teenager who sleeps fairly still and needs floor space for a desk. If they sprawl, the UK small double is 30cm wider at the same length, but we suggest at least 2.4m x 2.8m for it, so measure the room first.