360 degree swivel cushion

Available diameters range from about 12.5 inches to 18 inches, and common thicknesses run roughly 1 to just over 2 inches.

Many listings specify support around 300 pounds, while at least one listing specifies support up to 330 pounds.

Many cushions can be spot-cleaned or wiped down; several models also have removable, machine-washable covers for easier maintenance.

These cushions are described as lightweight and portable (weights range from about 1.32 to 3.88 pounds) and are designed for use in cars, office chairs, and other seating environments, including flat or contoured vehicle seats.

They are marketed to fit both flat and contoured vehicle seats and are described as compatible with most seating surfaces such as car seats, office chairs, and household chairs.

Swivel cushions rotate a full 360 degrees so users can pivot instead of twisting, reducing strain on the back, hips, and knees when entering or exiting seats. Reviews also note reduced caregiver effort when positioning or lifting someone into a car seat.