AliMed® Basic T-Foam™ Covered Wheelchair Cushion with "slow recovery" viscoelastic foam (also known as memory foam) offers optimal pressure distribution for wheelchair users. T-Foam molds to the body's contours and retains its compressed shape long enough to allow the user's capillary vessels to nourish tissues on the weight-bearing surface. When the user's body shifts or lifts even slightly, T-Foam slowly recovers its original shape. With its interconnected open-cell structure, T-Foam can absorb up to 90% of impact shock and vibration and provides better pressure distribution while allowing air to circulate freely through the material to prevent heat buildup and perspiration for cool, breathable comfort. It is also fire-retardant, exceeding CAL 117 specifications. Removable Black Polyknit cover is fully launderable. Available in three firmness ratings: Soft (T38), Medium (T41), and Hard (T47). Soft is recommended for general padding, while firmer grades are recommended for pressure relief.Select the proper height and firmness for optimal pressure distribution and molding without bottoming out. 2"H Soft: 0-100 lbs. Medium: 110-160 lbs. Hard: 120-150 lbs. 3"H Soft: 100-130 lbs. Medium: 140-170 lbs. Hard: 160-190 lbs. 4"H Soft: 130-160 lbs. Medium: 175-205 lbs. Hard: 175-205 lbs.