Sleepeezee ActivFlex Response 3600 Pocket Pillow Top Small Double 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
£1,199
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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
- Room to sprawl on your own: The UK small double is 30cm wider than the UK single, so a solo sleeper can stretch out, turn over or sleep diagonally without hitting the edge.
- Fits a compact double bedroom: We suggest at least 2.4m x 2.8m for the UK small double, which often leaves enough floor for a bedside table and a door that opens fully.
- Edges you can actually use: The high-density foam border around the springs keeps the sides steady, which means the full 120cm feels like sleeping space rather than a soft drop-off.
- Cushioning for a solo side sleeper: The medium soft pillow top and two Staycool Gel layers suit someone sleeping alone on their side, as there is no heavier partner's preference to balance.
- Workable for the odd guest couple: Two people can share the UK small double for a weekend stay, and the pocket springs help limit how much one sleeper's movement reaches the other.
This size suits you if...
You sleep alone and like plenty of room to spread out, your bedroom is a box room, loft conversion or small rental bedroom where a full double would crowd the door, or a couple only stays over now and then.
Consider another size if...
You share the bed with a partner every night, as two adults will feel cramped at 120cm wide. We'd recommend the UK double instead, which gives 67.5cm each; allow at least 2.6m x 2.8m.
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FAQ's
Is the Sleepeezee ActivFlex Response pillow top small double big enough for two?
For occasional stays, yes, and a guest couple will manage a weekend comfortably enough. For two adults every night it is tight. The UK double is 15cm wider at the same length and gives 67.5cm each, so it suits nightly sharing better, although we suggest at least 2.6m x 2.8m of room for it.
Will a UK small double pillow top mattress fit in a box room?
Often, yes. We suggest at least 2.4m x 2.8m for a UK small double, which many compact second bedrooms and studio flats meet. Measure from the wall to where the door swings, then allow for the frame, which adds a little to the 120 x 190cm footprint. In a loft conversion, check headroom on the side you climb in from.
Should a teenager move from a single to a small double mattress?
If they have outgrown a single, the UK small double adds 30cm of width without adding length, so the bed only grows sideways. Floor space is the trade-off: we suggest at least 2.1m x 2.8m for a UK single and 2.4m x 2.8m for a UK small double. The medium soft feel suits lighter bodies and side sleepers.
What sheets fit a 33cm deep UK small double mattress?
Buy 4ft fitted sheets with a deep pocket, as this mattress is 33cm deep and shallow sheets can spring off the corners. A standard double duvet covers a UK small double well. Check the frame too: a deeper mattress sits higher, so a base with a raised headboard or lip may suit it better.
Is a UK small double long enough if you're tall?
The UK small double is 190cm long, the same length as the UK single and UK double. If you're tall enough that your feet hang over a standard bed, the UK king is 10cm longer, although it is also 30cm wider and we suggest at least 2.7m x 2.9m of room for it.