www.metalyzer.com has no MX records.
Question and response
Question
dig www.metalyzer.com. MX
Answer
The response has no answer records.
Authority
metalyzer.com. 172800 SOA ns3.nsentry.de. hostmaster.metalyzer.com. 2017013000 86400 7200 3600000 172800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0