What We Like About This Drafting Stool The molded foam seat cushion is certainly the crowning point on this model. Firmer and more comfortable than typical foam fillings, it resists sagging over years of regular use. The 22-inch diameter base with casters is plenty wide for great support of the 13-inch seat. Drafting-height pneumatic swivel stool on dual-wheel casters * Five-point, reinforced nylon base with casters * 2-inch-thick, molded foam seat cushion with black upholstery * Lever-operated pneumatic height ranges from 18 to 26 inches