BEVCO's heavy-duty polyurethane Dura chairs are specifically designed for outstanding comfort and long-lasting use in the toughest work environments. The black polyurethane seat and back are anti-bacterial, impervious to water, oil, and most chemicals; puncture resistant and easy to clean. This articulating tilt model features simultaneous seat and back adjustments to properly position the angle of the chair for increased comfort during extended sitting durations. The contoured back is fully adjustable encouraging proper spinal alignment. The large waterfall seat aids in lower body circulation, improving overall wellness. The pneumatic height adjustment allows you to easily change your seat height from 16" - 21". This chair comes with a sturdy 25" diameter black nylon base. Model comes standard dual wheel hard floor casters.