DUO 400 Tall Back-Deep Seat
DUO™ 400 Tall Back
Tall-Back Dual Density Posture Support
The DUO™ 400 Tall Back combines the proven DUO™ Dual Density Posture Support Seat with the tallest backrest and larger seat configuration in the standard DUO range.
Its larger seating platform provides more room for users who need additional width and depth, while the tall backrest extends support further through the torso.
The seat retains the DUO principle of softer rear cushioning with a firmer front section, helping create a stable seat–pelvis interface for sustained desk-based work.
Upholstery
- Pure New Commercial-Grade ECO Wool upholstery - durable, breathable and sustainable
- IN-STOCK Colours : BLACKBUTT(Black) : VIOLA ( Navy Blue) : Oniscus CHARCOAL GREY - commercial grade Australian eco wool upholstery fabric.
- Special Custom Order - your choice of fabric and colour - wide range on offer
Key Features
- tall-back ergonomic task chair
- DUO™ Dual Density Posture Support Seat
- larger LS seat
- seat approximately 515 W × 500 D mm
- firmer front / softer rear split-cushion construction
- tall supportive backrest
- adjustable seat height
- forward / backward seat tilt
- adjustable backrest angle
- adjustable lumbar / back-height support
- intuitive adjustments accessible while seated
- commercial upholstery options
- AS/NZS 4438 compliant
- Certification: AFRDI Level 6
- 160 kg user weight rating
- 10-year warranty
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Support
Elevation
Angles
Tilt
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What this means for you when the 4 elements are aligned
| Corrected screen alignment → reduced neck strain | - S E E™ |
| Better pelvic support → less lower back fatigue | - S E A T™ |
| Arm positioning → reduced shoulder load | - A R M S™ |
| Movement support → reduces static load | - S P A S™ |
R E P O S E™ Outcome
The DUO™ 400 Tall Back supports Natural R E P O S E™ through larger seat geometry, pelvic stability and extended back support.
More seat space. Taller back support. The same pelvis-first DUO foundation.
- DUO™ Dual Density Posture Support Seat
- Seat Width 515mm
- Seat Depth 500mm DEEPER SEAT
- Seat Height 490-600mm
- Seat Tilt Range 12°
- Back 490 x 590mm TALL BACK
- Backrest Height 560-630mm
- 160Kg Weight Rated
Warranty: 10 Years
This product is supplied with a 10-year warranty covering defects in materials and workmanship when used under normal commercial office conditions. The warranty applies to structural and mechanical components. Normal wear and tear on soft or consumable elements is excluded.
DUO 400 Tall Back-Deep Seat
- DUO™ Dual Density Posture Support Seat
- tall supportive backrest
- larger LS seat
- firmer front / softer rear seat cushioning
- forward / backward seat tilt
- adjustable lumbar / back support
- can be economically Shipped Interstate - Compact Packing BOX
Who Is It For?
Suitable for users who:
- are taller or broader in build
- require a larger seat width and depth
- prefer a tall-back ergonomic chair
- want broader support through the upper torso
- spend extended periods working at a desk
- benefit from pelvic and lumbar support
- require adjustable seat and back positioning
- want the DUO support concept in its largest standard configuration
Problem to Solve
A chair can be highly adjustable and still be too small for the user.
If the seat is too narrow or shallow, the user may feel restricted and may not be able to distribute seated load comfortably across the full seat surface.
Likewise, a backrest that is too short may provide insufficient support for taller users.
The DUO 400 addresses both issues through a larger LS seat and tall backrest, while retaining the same pelvis-first DUO support principle.
Its Dual Density seat combines softer rear cushioning with a firmer front section to provide a more stable base beneath the pelvis.
S E A T™ — Primary
Support · Elevation · Angles · Tilt
The DUO 400 supports S E A T™ through:
- larger LS seat geometry
- Dual Density split-cushion construction
- softer rear pelvic cushioning
- firmer front seat support
- tall-back spinal support
- adjustable seat height
- forward / backward seat tilt
- adjustable backrest angle
- adjustable lumbar / back-height positioning
- controlled posture variation throughout the day
The objective is not simply a larger chair.
It is to provide appropriate seat dimensions, pelvic stability and back support for users who require more space and greater backrest coverage.
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DUO™ 400 Tall Back
Tall-Back Dual Density Posture Support
The DUO™ 400 Tall Back combines the proven DUO™ Dual Density Posture Support Seat with the tallest backrest and larger seat configuration in the standard DUO range.
Its larger seating platform provides more room for users who need additional width and depth, while the tall backrest extends support further through the torso.
The seat retains the DUO principle of softer rear cushioning with a firmer front section, helping create a stable seat–pelvis interface for sustained desk-based work.
Upholstery
- Pure New Commercial-Grade ECO Wool upholstery - durable, breathable and sustainable
- IN-STOCK Colours : BLACKBUTT(Black) : VIOLA ( Navy Blue) : Oniscus CHARCOAL GREY - commercial grade Australian eco wool upholstery fabric.
- Special Custom Order - your choice of fabric and colour - wide range on offer
Key Features
- tall-back ergonomic task chair
- DUO™ Dual Density Posture Support Seat
- larger LS seat
- seat approximately 515 W × 500 D mm
- firmer front / softer rear split-cushion construction
- tall supportive backrest
- adjustable seat height
- forward / backward seat tilt
- adjustable backrest angle
- adjustable lumbar / back-height support
- intuitive adjustments accessible while seated
- commercial upholstery options
- AS/NZS 4438 compliant
- Certification: AFRDI Level 6
- 160 kg user weight rating
- 10-year warranty
.png)

Support
Elevation
Angles
Tilt
.png)
What this means for you when the 4 elements are aligned
| Corrected screen alignment → reduced neck strain | - S E E™ |
| Better pelvic support → less lower back fatigue | - S E A T™ |
| Arm positioning → reduced shoulder load | - A R M S™ |
| Movement support → reduces static load | - S P A S™ |
R E P O S E™ Outcome
The DUO™ 400 Tall Back supports Natural R E P O S E™ through larger seat geometry, pelvic stability and extended back support.
More seat space. Taller back support. The same pelvis-first DUO foundation.
- DUO™ Dual Density Posture Support Seat
- Seat Width 515mm
- Seat Depth 500mm DEEPER SEAT
- Seat Height 490-600mm
- Seat Tilt Range 12°
- Back 490 x 590mm TALL BACK
- Backrest Height 560-630mm
- 160Kg Weight Rated
Warranty: 10 Years
This product is supplied with a 10-year warranty covering defects in materials and workmanship when used under normal commercial office conditions. The warranty applies to structural and mechanical components. Normal wear and tear on soft or consumable elements is excluded.




