The Black Diamond Ahwahnee Vestibule is constructed with lightweight, waterproof SilPoly fabric and adds 1.2 square meters (13 sq ft) of storage space to the Ahwahnee tent. Features: A lightweight, waterproof add-on vestibule for the Ahwahnee Tent Specs: Vestibule Area : 1.2 m² (13 sq ft) Average Vestibule Weight : 612 g (1 lb 6 oz) Black Diamond Ahwahnee Tent Ground Cloth