This screen enables you set the following parameters:

Multiple copies to multiple printers/trays

This option allows you to print documents to multiple printers or trays simultaneously. This is useful where you produce multiple copies of e.g. sales invoices, perhaps as different-coloured copies or you require special stationery for customers or internal use.

In order to print to different trays in the same printer you should set up multiple instances of the same printer on your machine, each with a different tray specified as the default.