Balt Circulation Task Chair, Black, 1 Carton Features a perforated pattern for excellent ventilation. Seat and back are injection-molded polypropylene contoured to provide a comfortable fit. Seat features a 16 slope to provide natural support, and is height adjustable from 17-Inch to 20-Inch. Includes a 5-star base with 2-Inch casters. Assembles in less than 15 minutes. GREENGUARD Indoor Air Quality Certified and GREENGUARD Children & Schools CertifiedSM.