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      Sleepeezee

      Amy Curtis

      Marketing Director, Sleepeezee

      What the Sleep Expert thinks...

      "For sink-in softness with serious tech underneath, choose ActivFlex 3600. Three spring tiers, ActivFlex™ foam and twin StayCool™ Gel layers align, contour and cool simultaneously. Mini springs in the pillow-top refine pressure relief, while the one-sided build keeps upkeep simple."

      For sumptuous full-body cushioning paired with innovative support, discover the Sleepeezee ActivFlex Response 3600 Memory Mattress, designed by the UK's leading sleep manufacturer.

      Innovative support for enhanced posture control

      A core unit of a combination of mini comfort springs and full-size traditional pocket springs provides targeted support to key areas of your body, ensuring you receive essential posture control. An innovative layer of ActivFlex™ spring foam combines the benefits of both of these supportive features, providing precise pressure relief to your body while effortlessly moulding to it like foam. These support systems, with an additional layer of up to 1000 mini comfort springs in the pillow top of this mattress, provide incredible support without compromising the soft feel of your sleep surface.

      Cooling comfort at every point of contact

      Also within the sumptuous pillow top layer of this mattress - which acts as a gorgeously comfortable mattress topper - is a layer of Staycool™ gel. This cooling gel actively draws heat away from your body, providing a consistently refreshing sensation from head to toe. In fact, you'll find two layers of this clever material within your Sleepeezee ActivFlex Response 3600 Memory Mattress, making it an exceptionally breathable, cool foundation for sleep.

      Full-body softness for a sink-in feeling

      Soft polyester comfort layers provide additional full-body cushioning, letting you enjoy that weightless 'sink in' feeling your body craves after a long, tiresome day. A luxuriously soft knitted cover finishes this mattress with a final touch of sumptuousness, while the one-sided, no-turn design of the mattress makes regular care a breeze.

      1278720-5063475047258

      3600 Pocket Springs icon
      3600 Pocket Springs
      Pocket springs are springs mounted in their own separate fabric pockets, meaning they work completely independently of one another and can provide your body with better pressure relieving support.
      Staycool™ Gel icon
      Staycool™ Gel
      Staycool™ Gel helps to manage moisture levels within the mattress, which aids temperature regulation so you won't feel too hot in warmer months.
       ActivFlex™ Spring Foam icon
      ActivFlex™ Spring Foam
      Designed to mimic the precise support and movement of pocket springs while moulding to your body as a foam, this innovative material combines the benefits of both.
      33cm Depth icon
      33cm Depth
      This mattress is approximately 33cm deep.
      Soft Knitted Cover icon
      Soft Knitted Cover
      Highly breathable and soft to the touch, this cover finishes the mattress with a truly luxurious feel.
      No Need To Turn icon
      No Need To Turn
      A single-sided mattress which does not need to be turned/flipped. One-sided mattresses should, however, be rotated head to toe regularly.
      Pillow Top icon
      Pillow Top
      Pillow top mattresses have the benefit of an additional pillow layer of plush fillings on the top of the mattress, which provides extra luxurious comfort.
      No Roll Together icon
      No Roll Together
      Individual personal sleeping zones mean that you won't be disturbed if your partner rolls or moves, as you won't feel their motion. There's also no tendency to roll towards the middle of the mattress.
      Pressure Relieving icon
      Pressure Relieving
      This type of mattress gives maximum pressure relief, allowing your body weight to spread across it evenly. This ultimately means less tossing and turning throughout the night and a more relaxing and restful sleep.
      Turning Handles icon
      Turning Handles
      Flag-stitched handles are attached to the sides of the mattress to assist in turning or rotating.
      Hypoallergenic icon
      Hypoallergenic
      Being hypoallergenic, this is the perfect item for allergy sufferers - or anyone looking for a healthy night's sleep.
      Vegan Friendly icon
      Vegan Friendly
      This product is made from materials that are 100% free from animal by-products.
      Made in the UK icon
      Made in the UK
      This item has been manufactured in the UK.
      Fire Resistant - Low Hazard icon
      Fire Resistant - Low Hazard
      This product conforms to the BS7177: 2008 standard for domestic use (low hazard) - ideal for use at home.

      Additional features

      • Made by an NBF-Approved ManufacturerPeace of mind and reassurance - the manufacturer of this item is an approved member of the National Bed Federation.
      • A combination of innovative springs target precise support to key areas of your body
      • Cleverly engineered ActivFlex™ spring foam provides an even closer level of support as it contours your shape
      • Staycool™ gel actively draws heat away from your body for consistent freshness through the night
      • The sumptuously soft pillow top design allows you to sink into the mattress with a weightless feel
      • Enhanced full-body cushioning ensures you stay blissfully comforted and properly supported all night long

      We provide our award-winning Free Next Day Delivery service to most locations, sending a proper night’s sleep out far and wide. Hassle-free and convenient, you can even choose a time and day that suits you, have us take your old mattress away for recycling, and get us to deliver to your room of choice!

      In some places, a small fee will be charged to help us get you your best night’s rest as quickly as possible. Take a look at the following postcodes to see if this applies to you, and if you’re not sure, then use our helpful Postcode Checker to help you shop with confidence.

      • AB10-AB16, AB21-AB25, AB30-AB39, AB41-AB45, AB51-AB56
      • CA1-CA9
      • DD1-DD11
      • DG1-DG14, DG16
      • EH1-EH49, EH51-EH55, EH91, EH95, EH99
      • FK1-FK21
      • G1-G5, G9, G11-G15, G20-G23, G31-G34, G40-G46, G51-G53, G58, G60-G79, G18-G84, G90
      • IV1-IV19, IV30-IV32, IV36
      • KA1-KA30
      • KY1-KY16, KY99
      • LA1-LA7
      • ML1-ML12
      • PH1-PH26
      • TD1-TD15
      100 Night Sleep Trial icon
      100 Night Sleep Trial
      Finding the perfect mattress shouldn't be stressful. That's why we offer a generous 100-night sleep trial. Snuggle in and test it out for at least 50 nights. If it's not your perfect match we’ll offer you an exchange for a mattress that you love even more.

      Sleepeezee 10 Year Guarantee

      Sleepeezee are confident that all of their beds and mattresses are made to the highest standards. Therefore they offer a 10 year guarantee across their entire range of mattresses and divan bed sets.

      Download warranty/guarantee information

      Sleepeezee ActivFlex Response 3600 Memory Mattress

      5.0 out of 5
      (1)
      (0)
      (0)
      (0)
      (0)
      3600 Pocket Springs
      ActivFlex™ Spring Foam
      Staycool™ Gel
      33cm Depth
      Soft Knitted Cover
      No Need To Turn
      Firmness: Soft
      100 Night Sleep Trial
      £719
      RRP £1039
      Save £320
      31% off
      from £719
      storage icon
      Single
      3' x 6'3"
      Lightning Deal
      £719
      storage icon
      Small Double
      4' x 6'3"
      Lightning Deal
      £969
      storage icon
      Double
      4'6" x 6'3"
      Lightning Deal
      £969
      storage icon
      King Size
      5' x 6'6"
      Lightning Deal
      £1079
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      Super King
      6' x 6'6"
      Lightning Deal
      £1389
      storage icon
      Super King Zip & Link
      6' x 6'6"
      Lightning Deal
      £1569
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      Free Delivery in Next Day

      Free delivery Tomorrow, 20th January

      Place your order now and we'll contact you to arrange delivery when your order is ready for despatch. You can then choose our popular next day delivery or select a day & time of your choice and get delivery when it's convenient for you.

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      Sleepeezee Sleep Expert

      See what the Sleep Expert thinks about this product. Find out

      Sleep Expert

      Rated Excellent

      5.0/5
      based on 1 reviews
      Trustpilot star rating
      Comfort Rating
      5 / 5
      100%
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      Reviews with images

      A customer photo for Sleepeezee ActivFlex Response 3600 Memory Mattress - After struggling with hip pain, changing our mattress to the sleepeezee activfle. Author: Customer. Dated: 2025-12-01
      Trustpilot Star rating Verified

      After struggling with hip pain, changing our mattress to the sleepeezee activflex 3600 response has been a real game changer! having the best nights sleep and sleeping through the night again!

      User Generated Content - An image regarding this review
      Customer 1st Dec

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      Sleepeezee ActivFlex Response 3600 Memory Mattress

      Sleepeezee ActivFlex Response 3600 Memory Mattress

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