VMS Help PRODUCT, Description  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    To use the POLYCENTER Software Installation utility from the DCL
    prompt, enter the PRODUCT command, a subcommand, a product name,
    and optional qualifiers. For example:

    $ PRODUCT INSTALL COBOL /VERSION=5.3

    You can use the PRODUCT commands in command procedure files.