Designed for comfort and durability, this chair is tailor made for larger sized or taller people up to 280 lbs. The ergonomically contoured molded foam seat is extra-thick with a waterfall edge for maximum comfort. Pneumatic height control raises and lowers the chair quickly. The included armrests are height and width adjustable. Additional features include dual wheel casters and a 26" diameter polished aluminum base. Seat cushion is 22"w x 21"d x 4" thick. Backrest is 21"w, 3½" thick and rises 22" above the seat.Office model height adjusts from 24" to 28".Drafting model includes CK49 height extension kit and adjusts from 31½" to 35½".