American Seating inherited production of the wood and cast iron “Combination” chair/desk from Grand Rapids School Furniture Company. In 1911, an updated Combination known as the “101” made use of tubular steel. Other models introduced such features as adjustable height, swivel seats, and bases that didn’t need to be bolted to the floor. All of these elements were incorporated into the 1921 “Universal,” which was scientifically designed to promote good posture, and stayed in production for decades. Post-World War II designs made use of new materials such as plywood, plastic, and plastic laminate.