Designed by Giancarlo Piretti, Doni provides optimal comfort with hip-articulation and body-conforming curves. The backrest and seat are injection-molded polypropylene, which can be one or two colors. The seat and backrest are joined by a pair of hidden articulation mechanisms, each consisting of a 14-gauge steel housing, twin 7-gauge levers and steel coil springs. While maintaining a one-piece shell appearance, this mechanism allows the backrest to recline up to 17 degrees of motion.