diff --git a/app/models/channel/driver/mail_stdin.rb b/app/models/channel/driver/mail_stdin.rb
index e5e3354e4..d8aa0b849 100644
--- a/app/models/channel/driver/mail_stdin.rb
+++ b/app/models/channel/driver/mail_stdin.rb
@@ -16,6 +16,10 @@ e. g. if you want to trust on mail headers
 
   cat test/data/mail/mail001.box | rails r 'Channel::Driver::MailStdin.new(trusted: true)'
 
+e. g. if you want to process this mail by using a certain inbound channel
+
+  cat test/data/mail/mail001.box | rails r 'Channel::Driver::MailStdin.new(Channel.find(14))'
+
 =end
 
   def initialize(params = {})