Library /sys$common/syshlp/nclhelp.hlb create, x25_protocol, dte, pvc, packet_size  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Packet size, in octets, for the PVC. This argument determines
    the value of the packet size characteristic. This value should
    be within the maximum and minimum packet size specifier by the
    parent DTE.