The Functional Forms "U" Shaped Block provides side and bottom forearm support while in the prone position.Made of anti-bacterial/anti-fungal, water resistant, breathable nylon that is made specifically for health care applications and is easy to wipe clean with neutral soap suds and lukewarm water. Then rinse and dry. Soft, washable anti-slip surface on bottom. Meets CAL 117 fire regulations. No latex. Also available in soft vinyl.