Clicking this button sends the MLS numbers in your current list to the MLS. Be sure the host is expecting to receive them before you send them. That is, be sure you are in an MLS command sequence where the remote host is ready for you to type in one or more MLS numbers. This button saves you the bother of having to write down MLS numbers you see on the screen and type them in again later. (This button works only if you are currently online in the Terminal window. Otherwise, it displays an error message.)