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