The CapTel 200 phone may be used with a DSL (Digital Subscriber Line) as long as a “DSL filter” is placed on the line between the CapTel 200 and the DSL connection. DSL filters are very common, and are placed on all telephones in a home where DSL service is connected. Your DSL provider supplies these filters at the time of connection. In some cases, DSL subscribers may elect to have a “Whole House” filter installed; whole house DSL filters are compatible with the CapTel 200. If you have or are considering DSL, please check with your DSL provider to make sure you have the proper DSL filter.