52.209.242.188
ec2-52-209-242-188.eu-west-1.compute.amazonaws.com
52.213.70.140
ec2-52-213-70-140.eu-west-1.compute.amazonaws.com
52.48.111.39
ec2-52-48-111-39.eu-west-1.compute.amazonaws.com

in1-smtp.messagingengine.com.
in2-smtp.messagingengine.com.