To optimize email deliverability, the domain in the FROM address must match the domain the email is signed with. That domain will always be "haulix.com."

The REPLY-TO address will always be the email address you choose. As the name suggests, when the recipient hits the 'Reply' button, it will automatically route to your address.

In the example below, 'JohnSmith@missionpr.com' is the Reply-To address. When a subscriber clicks 'Reply', the reply message is sent to 'JohnSmith@missionpr.com' and not 'missionpr@haulix.com'. 

From: missionpr@haulix.com

To: editor@pitchfork.com

Reply-To: JohnSmith@missionpr.com