The Original Evolution Stability Ball Chair leads the pack as an ergonomic, reliable and safe active seating option. Ideal for all home and office use where improved posture, core strength and overall back health is the goal. Improved posture and core strength can reduce back pain and sitting fatigue. The original Evolution Ball Chair Kit includes a high quality height adjustable base (risers included additional height), anti-burst stability ball, standard casters, pump, and “Just Move It” exercise poster. Optional Cozy Covers and Ice Casters available in the Premium and Sherpa Ball Chair Kits.