SEY 690, designed by Emilio Nanni for Billiani, is a stackable armchair that features a sturdy and enveloping lacquered metal frame with an upholstered seat shell in fabric. The lightweight frame has a clean, minimalist design that expresses at once both a reassuring and innovative concept. Another version, the SEY 691 outdoor stackable armchair is also available, featuring a shell in coloured nautical rope.