/SIZE = [n]

    The logical volume size is recorded in the save-set header during
    a backup operation. By default, during a restore operation, the
    logical volume size is not preserved because restoring a save
    set of 2 GB to a 4-GB disk, for example, results in only 2 GB of
    available disk space.

    The /SIZE qualifier, however, allows you to preserve the logical
    volume size on the target device. Alternatively, you can specify
    the logical volume size of the target device by using the
    optional keyword value n.