Purview DLP rule conditions - Any External email address

im trying to trigger a prompt or notification to the user sending an email with an attachment to any external email address, but I dont seem to be able to find a condition that matches, my first go to was a condition that is NOT the company [domain.com](http://domain.com) but all I can seem to find is "recipient domain is" which doesnt help when trying to catch any possible external email address. I have tried to google, but it seems the responses are out of date as the options arent there, perhaps for exchange online before it all moved to purview, im not sure. Any suggestions?