Identify Your Reader
A cover letter should be addressed to a person receiving correspondence or a package in which a number of items have been included. That person's name should be placed in the inside heading and salutation of your cover letter. It should also be included on the top line of your envelope.
Remember that people do business with people first, businesses second. When you address your reader by name, you recognize their importance and value as an individual human being. In the inside heading of the sample cover letter, the reader is identified by both name and position.