The products listed here include both principal and auxiliary equipment and materials used at hydro facilities. Product vendors are listed alphabetically within each category. To contact companies, refer to the Company Listings. The “RS#” reference that appears after some listings provides a way to obtain information from companies that have advertised in this issue. Tear out the reader service card between pages 56 and 57, circle appropriate companies’ numbers, and mail or fax the card to HCI Publications.