Robtex

Up: 72.133.128.0/17
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IP	Type	Hostname
72.133.144.82	PTR	mta-72-133-144-82.wi.rr.com
72.133.167.3	PTR	mta-72-133-167-3.wi.rr.com
72.133.167.65	PTR	mta-72-133-167-65.wi.rr.com
72.133.167.129	PTR	mta-72-133-167-129.wi.rr.com
72.133.168.67	PTR	mta-72-133-168-67.wi.rr.com
72.133.168.128	PTR	mta-72-133-168-128.wi.rr.com
72.133.168.130	PTR	mta-72-133-168-130.wi.rr.com
72.133.169.184	PTR	mta-72-133-169-184.wi.rr.com
72.133.171.65	PTR	mta-72-133-171-65.wi.rr.com
72.133.171.131	PTR	mta-72-133-171-131.wi.rr.com
72.133.171.192	PTR	mta-72-133-171-192.wi.rr.com
72.133.176.1	PTR	mta-72-133-176-1.wi.rr.com
72.133.176.2	PTR	mta-72-133-176-2.wi.rr.com
72.133.176.67	PTR	mta-72-133-176-67.wi.rr.com