The nitrile rubber coated comfort coils provide foot, ankle, leg and lower back support. They have over a ninety percent re-compression rate, helping preserve the ergonomic benefits over the life of the product. This mat is oil and grease resistant. USA made. The nitrile rubber layer helps prevent tearing. This mat has uperior leg, back and foot support. This mat is accepted by the American Podiatric Medical Association. 55in long by 33in wide