Sleepeezee ActivFlex Response 1600 Memory Mattress
Mattress
Sleepeezee ActivFlex Response 1600 Memory Mattress
Size
Firmness
Construction
Depth (cm)
25
Layers
5
Layer Details
- Soft Knitted Cover. A highly breathable knitted cover that's soft to the touch. It gives the mattress a genuinely luxurious finish.
- Pillow Top / Comfort Layer. A soft polyester comfort layer that adds gentle cushioning, which means the surface feels welcoming rather than hard. It does this without compromising the firm feel underneath.
- Staycool™ Gel. A deep layer of Staycool Gel that provides a consistently cooling sensation, helping to regulate your temperature. If you're a hot sleeper, this is the layer doing the work for you.
- ActivFlex™ Spring Foam. A layer of spring foam that behaves like pocket springs for precise support, yet moulds to your body like foam. The result is support at every point of contact rather than pressure in a few places.
- Pocket Springs Core. A core of up to 1600 barrel-shaped pocket springs delivering targeted support to key areas of your body. This is where the firm feel comes from.
Layer details from mattressnextday.co.uk product page, September 2026.
- Space for one, on your terms: At 120cm wide the UK small double is 30cm wider than the UK single, so you can stretch, roll and change position freely.
- A firm mattress that fits a small room: It's 15cm narrower than the UK double, which often decides whether a box room or loft conversion still has a walkway beside the bed.
- Cooling that matters in tight spaces: Compact rooms warm up quickly, and the Staycool Gel layer helps regulate your temperature where a foam-heavy mattress might feel stuffy.
- Firm support across the full width: The pocket spring core supports you edge to edge, so a solo sleeper can use all 120cm rather than drifting back to the middle.
- Easy to dress: 4ft is a standard UK size, so small double fitted sheets are simple to find, and a standard double duvet drapes generously over it.
This size suits you if...
You sleep alone and have outgrown a UK single but your room can't spare the width of a full double, or you're furnishing a guest room or holiday let where couples stay occasionally rather than nightly. It also suits a teenager who needs more bed without losing the floor space they still use, provided they get on with a firm feel.
Consider another size if...
You share the bed every night, since 120cm is tight for two firm-mattress sleepers who can't sink towards each other. 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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Is a small double big enough for one adult on the ActivFlex Response 1600?
Comfortably, yes. The UK small double is 30cm wider than the UK single, which on a firm mattress like this makes a real difference: you can spread out or sleep diagonally without an arm hanging over the edge. The pocket spring core supports you right across the surface, so none of that width is wasted.
Will the Sleepeezee ActivFlex Response 1600 small double fit in a box room?
Often, and that's its main appeal. At 120 x 190cm we suggest a room of at least 2.4m x 2.8m, which leaves space to walk round and open the door. Measure before you buy, because being 15cm narrower than the UK double is frequently what decides whether the layout works at all.
Can a couple share the ActivFlex Response 1600 in a small double?
For occasional nights, yes, which makes it a sensible guest room choice. For every night, 120cm is a squeeze, and because this is a firm mattress you won't sink towards the centre; you'll each feel the limited width. Couples sharing nightly would be happier on the UK double, which is 15cm wider.
What bedding does the small double ActivFlex Response 1600 take?
You'll need small double, or 4ft, fitted sheets, as UK single and UK double sheets won't sit properly on a 120cm width. For the duvet, a standard double works well and gives a generous overhang on each side. Since 4ft is a standard UK size, none of this is hard to find.
Is the small double or the UK double better for a teenager's room?
Usually the UK small double. It gives a teenager who has outgrown a UK single a proper adult-width bed while taking 15cm less width from the room, which often preserves desk or floor space. The firm feel here suits growing sleepers who want support, though very lightweight side sleepers may find it a little unforgiving.