How to write multiple values using 800xA Push Button

I'm wondering how to use the ExtendedWrite input within the basic 800xA Push Button to write multiple values to multiple targets. Looking into the PB Object, the ExtendedWrite is of the data type WriteSpecification, which is referenced on page 216 of 3BSE049230-510 E, but I am not able to discern from this documentation how to actually employ this function. I've come up with an alternate way of accomplish this by using item hosted inputs, but I'm still curious about how to use this apparent feature along with the WriteSpecification() data type.