20 is for furniture, mirrors, picture frames, and goods not included in other classes made of wood, cork, reed, cane, wicker, horn, bone, ivory, whalebone, shell, amber, mother-of-pearl, meerschaum, and substitutes for all these materials, or of plastics. This class includes metal furniture and furniture for camping, bedding (for example, mattresses, spring mattresses, pillows), looking glasses and furnishing or toilet mirrors, registration number plates not of metal, and letter boxes not of metal or masonry.