What is "From" parameter for - Convert-SPWebApplication -Identity " http://site " -To Claims –RetainPermissions -Force?

Hi there,

When I run 
Convert-SPWebApplication -Identity " http://HAYSPSRV2013:82 " -To Claims –RetainPermissions -Force

It is asking me to supply value fro "From" parameter.

What will I type in there?

Thanks so much.