Part of Mater’s Circular Materials initiative, Eternity adds a comfy upholstered seat to its sustainably minded construction and supportive ergonomics. Designed by studio Space Copenhagen, the molded shell highlights an innovative material that mixes upcycled coffee-bean leavings with recycled plastic industrial waste in an attractive off-black hue. Fully stackable, the chair’s rounded contours get extra ease from the cushioned seat in a choice of stocked fabric options.