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Black rectangular memory-foam seat cushion with leather finish and U-shaped cutout, 18 by 20 inches

Uncaged Ergonomics Ergonomic Seat Cushion X-Large 18 x 20 in Black

SKU CH-DBKW-KDYGC

Extra-large memory-foam cushion with U-shaped cutout relieves sciatica and tailbone pressure during long sitting sessions

  • Features15% Larger and Wider for more Comfort and Support. Seat Cush
  • ColorBlack
  • Finish/SurfaceLeather
  • Sizes/Dimensions1
  • Specifications18 L x 20 W x 0.1 H inches, Memory Foam, Black, X-Large, 15%
  • Type SpecificationsDesktop
  • Relieves sciatica and tailbone pain instantly with charcoal-infused memory foam
  • Extra large size is 15% wider and thicker than standard cushions for full hip-to-thigh coverage
  • Doctor-recommended for posture and spinal alignment during long sitting sessions
  • Removable washable cover with carrying handle for portable use on chairs, car seats or wheelchairs
  • Premium comfort foam resists flattening to maintain shape and support over time

Extra-Large Ergonomic Seat Cushion

This extra-large ergonomic seat cushion measures 18 x 20 inches and is designed for office workers, drivers and wheelchair users who need extended pressure relief. The 15% larger surface accommodates wider hips and thighs without compressing flat. Charcoal-infused memory foam targets the coccyx to ease sciatica and lower back pain during long sitting sessions.

Charcoal Memory Foam with Removable Cover

Premium charcoal-infused memory foam resists flattening and maintains its shape under continuous weight. A U-shaped cutout lifts the tailbone off the seating surface to redistribute pressure. The black leather-finish cover is removable and machine-washable, and a built-in carrying handle makes it simple to move between desk, car and wheelchair.

Orthopedic Support for All-Day Comfort

The cushion is 0.1 inches thick and engineered to promote healthy spinal alignment while correcting slouching posture. Weight is distributed evenly across the surface to reduce fatigue and improve circulation during extended use. It fits most standard chairs and requires no setup beyond placing it on the seat.

Highlights

  • Relieves sciatica and tailbone pain instantly with charcoal-infused memory foam
  • Extra large size is 15% wider and thicker than standard cushions for full hip-to-thigh coverage
  • Doctor-recommended for posture and spinal alignment during long sitting sessions
  • Removable washable cover with carrying handle for portable use on chairs, car seats or wheelchairs
  • Premium comfort foam resists flattening to maintain shape and support over time

Specifications

BrandUncaged Ergonomics
Features15% Larger and Wider for more Comfort and Support. Seat Cushion, Orthopedic Cushion for Sciatica, Carrying Handle, Washable and Breathable Cover, Removable Cover cushion for office chair, Portable memory foam car seat cushion, chair cushion for office chair, office desk accessories, Memory Foam, 100% Breathable Cotton, Remove Inner and Outer seat cover from the core (premium memory foam). Cover is machine washable on a gentle cycle with cold water. DO NOT PUT MEMORY FOAM IN WASHER OR DRYER., Sitting
ColorBlack
Finish/SurfaceLeather
Sizes/Dimensions1
Specifications18 L x 20 W x 0.1 H inches, Memory Foam, Black, X-Large, 15% Larger and Wider for more Comfort and Support. Seat Cushion, Orthopedic Cushion for Sciatica, Carrying Handle, Washable and Breathable Cover, Removable Cover cushion for office chair, Portable memory foam car seat cushion, chair cushion for office chair, office desk accessories, Remove Inner and Outer seat cover from the core (premium memory foam). Cover is machine washable on a gentle cycle with cold water. DO NOT PUT MEMORY FOAM IN WASHER OR DRYER., Charcoal Infused Memory Foam, 100% Breathable Cotton, SitCushion, 2025-Se
Type SpecificationsDesktop

Questions about this item

What are the exact dimensions of this X-Large seat cushion?

The cushion measures 18 inches long by 20 inches wide with a 0.1 inch height profile.

What chair types does the 18 x 20 inch cushion fit?

The extra-large dimensions suit most office chairs, car seats and wheelchairs that can accommodate an 18 by 20 inch seating surface.

How do you install the cushion and which side faces up?

Place the cushion on the seat with the U-shaped cutout at the rear so your tailbone rests in the opening, then secure the removable cover if it has shifted.

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