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ComparisonLast updated on 9 July 2025

Sleeping Duck vs Ergoflex

Easily compare the Ergoflex vs Sleeping Duck Mattresses side-by-side.

Sleeping Duck Mach II mattress on Mattress Zone Australia
Ergoflex 5G mattress - Mattress Zone Australia
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At a glance

Recommended For
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What we like
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Keep in Mind
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Essential Mattress Info

Brand
Sleeping DuckErgoflex (Australia)
About
Unlike most mattresses, Sleeping Duck Mach II is not one size fits all as you can customise each mattress side.
  • The original mattress-in-a-box brand, with a 10-year warranty that is tried and trusted
  • First to launch in Australia
  • Recommended by the Australian Back Doctor
  • Supporting families of domestic violence for over ten years
Mattress Type
Hybrid (foam & springs)Memory foam
Prices
Video
Certifications
CertiPur-US®
✕CertiPur-US®
OEKO-TEX®
✕OEKO-TEX®

Trial & Warranty

Trial Period
✓✓
Trial Period (nights)
10030
Warranty Length (years)
1010

Firmness Options

One Firmness Fits All?
✕✓
Adjustable Firmness
✓✕
Half-Half Firmness
✓✕
Selectable Firmness
✓✕
Flippable / Reversible Firmness
✕✕
Firmness Info
Firmness is the most sensitive and personal element of any mattress. Sleeping Duck have re-engineered the traditional mattress to make it modular, allowing you to pick (and even swap) the firmness that's exactly right for you. Simply choose between medium or firm initially. Rest assured, you'll be able to change the firmness via foam swaps for the first 100 nights for free.
Medium:
  • Suitable for side sleepers
  • Sinks in slightly while being supportive
  • Approximately a 6/10 on the firmness scale.

Firm:
  • Suitable for back sleepers
  • Still feels cloud like while maintaining a strong level of support
  • Approximately an 8/10 on the firmness scale.

Half Medium & Half Firm:
  • A different firmness on either side of the bed
  • Ideal for couples who have different firmness preferences.
The Ergoflex mattress is a result of over a decade of research and development. This one 'perfect' mattress is rated medium-firm and is optimised with the highest-quality materials available, and has thousands of 5-star reviews from customers in Australia, the UK, and all over the globe.

Mattress Construction

Materials Overview
The Sleeping Duck is made for sleepers who want the best of old and new. The Sleeping Duck is Australian designed and combines a combination of technologies in the one mattress:
  • Australian made AntiGravity surface foam (made from high density AirGrown polyurethane foam)
  • Australian made Precision Firmess Pads (made from high density AirGrown polyurethane foam)
  • The Motherboard: a multi-zoned steel spring system
These elements create a highly comfortable, breathable and supportive mattress on both the lumbar and neck.
This award-winning, GECA certified mattress is loved by their customers.
As the most premium mattress in a box in Australia, the Ergoflex™ 5G comprises of the following layers:
  • Luxurious Tencel® Cover
  • Protective Inner Cover
  • 9cm High Density Visco-Elastic Memory Foam (Density: 85kg/m³)
  • 5cm Cool-Sleep Foam
  • 9cm High-Resilience Foam Base.
Comfort Info
Appreciating that everyone is different, Sleeping Duck allows you to choose from a medium or firm mattress (or half-half on Queen and King sizes). Over the course of your 100 night trial you can change the firmness of your mattress depending on the way you are sleeping. These firmnesses can be adjusted with just the pull of a zip.
The ComponentAdapt customisation system empowers you to take full control of the comfort of your mattress. This is achieved via interchangeable Precision Pads that you can swap out for both you and your partner. After sleeping on your mattress, you can contact the SDHQ who can help you to customise and adapt the mattress with up to 256 combinations possible.
Ergoflex is comparable only to TEMPUR®, yet it is technically more advanced and superior in performance to every alternative both in this price range and beyond. As a result it is renowned for delivering deep restorative sleep. The OEKO-TEX® Standard 100 certification makes it a great option for asthma and allergy sufferers as the mattress is resilient to the growth of bacteria, moulds, mildew and fungi. Class-leading zero disturbance technology promotes deeper, more restful sleep as it reduces the likelihood of being woken by a restless sleeping partner. Just watch the video above to see how little disturbance is caused by a parachuter landing on the mattress (spoiler: the wine glass doesn't even fall over!)
Support Info
The Sleeping Duck Mach II has a multi-zone support structure to make sure every part of your body is wonderfully supported and comfortable. Pocket Springs are far more resilient and provide better support over a longer period of time. They're specifically designed to ease the human body to relaxation and relieve pressure points by varying the distribution of weight throughout the entire surface.
The mattress has superior edge support thanks to the reinforced spring perimeter through the use of 2.3mm springs on the entire border. This allows you to sleep edge-to-edge, making your Queen size feel like a King, and allowing you to sit or sleep on the edge without the rolling or sliding off feeling.
Independently pocketed springs create zero disturbance between you and your sleeping partner.
The Ergoflex 5G mattress is the only true high density memory foam mattress available. Designed to mould itself to the contours of your body it provides instant comfort, more support and orthopaedic pressure-relief. It is recommended by Practioners for those that suffer from back pain, fibromyalgia, circulation problems and joint complaints or to those simply in need of a good night's sleep.
Comfort Specs
AntiGravity Foam
The top layer was engineered in pursuit of the ultimate comfort. The foam which doesn't contain any latex or memory foam offers superior comfort and cushioning. It actually improves on the combination and provides increased pressure relief, buoyancy and breathability. The hyper-adaptable properties of the AntiGravity foam allows it to rapidly reshape around you as you move, allowing unimpeded movement, not achievable with the more rigid moulding that memory foam provides. It is produced via pressure expansion rather than chemical reactions which means it is 8x more open than latex and memory foam. Furthermore, it's all Australian made.
The use of the pocketed springs allows for far superior air circulation and ventilation than all-foam mattresses. This helps to keep your mattress cooler and drier.
High Density Visco-Elastic Memory Foam
The foam design has billions of ball-shaped open cells that give added breathability than traditional memory foams which have been known to sleep hot. Cool-Sleep Foam
This unique Cool-Sleep airflow system encourages air to freely circulate thorough the mattress keeping you cool while you sleep. It does this by using a specially-engineered foam design that instead of being a rectangular block of foam it more resembles an upside down egg carton, which has channels for temperature-regulation. These work in combination with the 3D mesh panels in the outer cover to disperse heat.
Support Specs
The combination of the changeable, high-density foam layer and the individually-wrapped pocketed spring multi-zone support layer, creates a system that is highly responsive to your needs.
The multi-zone spring system has three types of springs that are specifically engineered - 2.3mm springs around the very edge, 2.0mm springs through your back and hip zones and 1.8mm springs through your shoulder zone. The shoulder and hip zones conform whilst more support is provided to the lower back and head zones, therefore giving you the required alignment for a restorative night's sleep.
The use of these Twice Tempered IndestructSprings is not just for their ductility, strength and durability properties but to provide comfort and support through proper spinal alignment.
High Density Visco-Elastic Memory Foam
This comfort layer gives the optimum level of support, shifting responsively to your movements. You will experience a feeling of pure weightlessness as every part of your body is supported and cradled which alleviates pressure points (such as your hips, back, and shoulders). High-Resilience Foam Base
This base layer provides the precise support for the upper foam layers and gives the mattress its performance longevity. Ergoflex mattresses stand up to their warranty claims - Ergoflex's ten-year guarantee is underpinned with the confidence of having had more than a decade of success and continuing.
Fabric Specs
BreatheTech Cover
The vortex spun bamboo yarn top cover is designed for maximum breathability and ease of switching foam layers. Soft and silky to touch, it also has natural anti-microbial properties that keep it fresher for longer. The cover easily unzips and is machine washable. Plus no annoying buttons that you feel with tufted mattresses. This high performance bamboo yarn is knitted to ensure optimal breathability for air and liquid, to ensure it remains dry and cool.
Luxurious Tencel® Cover
This Tencel® outer cover provides a natural, antibacterial and breathable sleep surface. Tencel is sustainable an outperforms natural cotton in terms of moisture-wicking and breathability. It can also be removed and is machine-washable at 30°. The cover also has vented 3D mesh panels at each end to allow heat to escape. Protective Inner Cover
This super fine inner cover protects the core foam layers.
Manufactured in
ChinaChina

Suitability

Side Sleepers
✓✓
Back Sleepers
✓✓

Size & Weight

Single
✓✓
Single Dimensions
188 x 92 x 31 cm187 x 92 x 23 cm
Single Weight (kg)
3024
King Single
✓✓
King Single Dimensions
203 x 107 x 31 cm203 x 106 x 23 cm
King Single Weight (kg)
3628
Double
✓✓
Double Dimensions
188 x 138 x 31 cm187 x 137 x 23 cm
Double Weight (kg)
4337
Queen
✓✓
Queen Dimensions
203 x 153 x 31 cm203 x 152 x 23 cm
Queen Weight (kg)
5239
King
✓✓
King Dimensions
203 x 183 x 31 cm203 x 183 x 23 cm
King Weight (kg)
6541
California King
✓✕
California King Dimensions
203 x 203 x 31 cm✕
California King Weight (kg)
74✕

Delivery

Delivery Cost
FREEFREE
Delivery Info
Free next business day for almost all of Australia or choose your preferred delivery date and time. Delivered straight to your door.
Free next day delivery to Brisbane, Canberra, Melbourne and Sydney and express delivery Australia wide. Every Ergoflex is delivered right to your door in a beautifully compact box. Ergoflex were the first to deliver mattresses this way, and like all excellent ideas it's now an industry standard. Note: free mattress returns not applicable to all locations.
Prices
Latest Promotions

Independence Day Sale - ends Sunday - $200 off all stock. Code: 4JULY2025

See offer

Save $225 with code : TAKE25

See offer