+.It Fl o Ar ssh_option
+Can be used to pass options to
+.Nm ssh
+in the format used in the
+.Xr ssh 1
+configuration file. This is useful for specifying options
+for which there is no separate
+.Nm sftp
+command-line flag. For example, to specify an alternate
+port use:
+.Ic sftp -oPort=24 .
+.It Fl s Ar subsystem | sftp_server
+Specifies the SSH2 subsystem or the path for an sftp server
+on the remote host. A path is useful for using sftp over
+protocol version 1, or when the remote
+.Nm sshd
+does not have an sftp subsystem configured.
+.It Fl v
+Raise logging level. This option is also passed to ssh.
+.It Fl B Ar buffer_size
+Specify the size of the buffer that
+.Nm
+uses when transferring files. Larger buffers require fewer round trips at
+the cost of higher memory consumption. The default is 32768 bytes.