Office Star Thick Padded Vinyl Seat Backless Drafting Stool, Black, 17.25-24.5-Inch Heigh Adjustable Pneumatic Drafting Backless Stool with Nylon Base Dual Wheel Carpet Casters Height Adjustment 17.25" to 24.25" Seat dimensions: 13.5 inches wide x 13.5 inches deep x 2.75 inches thick