This industry comprises establishments primarily engaged in the merchant wholesale distribution of professional equipment and supplies (except ophthalmic goods and medical, dental, and hospital equipment and supplies). Merchant wholesale distribution of professional equipment, instruments, and/or goods sold, prescribed, or used by ophthalmologists, optometrists, and opticians, such as ophthalmic frames and lenses, and sunglasses,--are classified in Industry 423460, Ophthalmic Goods Merchant Wholesalers; Merchant wholesale distribution of medical professional equipment, instruments, and supplies used by medical and dental practitioners (except ophthalmic equipment, instruments, and goods used by ophthalmologists, optometrists, and opticians) and medical facilities--are classified in Industry 423450, Medical, Dental, and Hospital Equipment and Supplies Merchant Wholesalers; Merchant wholesale distribution of silverware and plated flatware--are classified in Industry 423940, Jewelry, Watch, Precious Stone, and Precious Metal Merchant Wholesalers; Merchant wholesale distribution of books--are classified in Industry 424920, Book, Periodical, and Newspaper Merchant Wholesalers; and Merchant wholesale distribution of school furniture--are classified in Industry 423210, Furniture Merchant Wholesalers.