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

       /PRODUCT=(product-name[,...])

    Selects products with the specified product name.

    Parentheses (())  are optional only when you specify a single
    product name. They are required when you specify multiple product
    names.