A stackable chair has a frame with a tubular crosspiece, to each end of which a monolithic casting having legs and a backrest supportand, optionally, an armrestis attached by means of an integral connecting boss received within the crosspiece and held in place by a connector pin. The backrest supports...http://www.google.com.au/patents/US6481789?utm_source=gb-gplus-sharePatent US6481789 - Stackable chair
