66.151.73.15.
Question and response
Question
dig mail.har.com. PTR
Answer
mail.har.com. 300 PTR 66.151.73.15.
Authority
har.com. 3600 NS ns-1380.awsdns-44.org.
har.com. 3600 NS ns-1987.awsdns-56.co.uk.
har.com. 3600 NS ns-229.awsdns-28.com.
har.com. 3600 NS ns-612.awsdns-12.net.
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0