The Stand Up Desk Store Stackable Adjustable-Height Classroom Stool - Black, 2-Pack takes the classic metal shop stool design and makes it ideal for education. That means this lab stool is compliant with all key requirements for educational furniture. Certifications include CPSIA, TSCA Title VI, CARB P2, and ANSI/BIFMA X5.1-2017 (for general-purpose office chairs). It offers a top pad covered in acid-free vinyl (phthalate free). The steel shop stool is also free of lead, cadmium, mercury, and hexavalent chromium. SUDS stackable stools for the classroom can be stacked up to 6 high. Steel construction and a durable powder coat finish ensures years of dependable use. Overall dimensions are 25" D x 25" W x 19" to 31.8" H. Seat height range is 19" to 31.8" H (in 1" increments). Seat diameter is 14". Available as a single chair or 2-pack. 5-year limited warranty against defects. Stand Up Desk Store is based in the suburbs of Chicago.