Clean room stool ergonomically designed production chairs and stools provide hours of comfortable seating. Standard on all seating: 18″ sq. Seat, 16″w x 13″h back with 2-1/2″ thick foam padding, adjustable seat depth and reinforced black nylon bases with dual-wheel casters. Pneumatic height adjustment from 19 to 27″ for stools. Stool has adjustable chrome plated foot ring. Conductive clean room models meet class 100, federal standard 209e. They have a three level filtration system, completely sealed cushions and chrome plated metal parts. Only the non-esd fabric chairs are scotchgard treated. Easy assembly.