Robtex

Up: 72.135.64.0/18
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Down left: 72.135.64.0/20
Down right: 72.135.80.0/20

IP	Type	Hostname
72.135.67.65	PTR	mta-72-135-67-65.kc.rr.com
72.135.67.160	PTR	mta-72-135-67-160.kc.rr.com
72.135.67.193	PTR	mta-72-135-67-193.kc.rr.com
72.135.71.99	PTR	mta-72-135-71-99.kc.rr.com
72.135.71.161	PTR	mta-72-135-71-161.kc.rr.com
72.135.71.193	PTR	mta-72-135-71-193.kc.rr.com
72.135.72.0	PTR	mta-72-135-72-0.kc.rr.com
72.135.72.1	PTR	mta-72-135-72-1.kc.rr.com
72.135.72.2	PTR	mta-72-135-72-2.kc.rr.com
72.135.72.162	PTR	mta-72-135-72-162.kc.rr.com
72.135.73.2	PTR	mta-72-135-73-2.kc.rr.com
72.135.73.99	PTR	mta-72-135-73-99.kc.rr.com
72.135.73.162	PTR	mta-72-135-73-162.kc.rr.com
72.135.76.227	PTR	mta-72-135-76-227.kc.rr.com
72.135.78.0	PTR	mta-72-135-78-0.kc.rr.com
72.135.78.33	PTR	mta-72-135-78-33.kc.rr.com
72.135.78.35	PTR	mta-72-135-78-35.kc.rr.com
72.135.78.64	PTR	mta-72-135-78-64.kc.rr.com
72.135.78.225	PTR	mta-72-135-78-225.kc.rr.com
72.135.79.35	PTR	mta-72-135-79-35.kc.rr.com
72.135.79.162	PTR	mta-72-135-79-162.kc.rr.com
72.135.80.2	PTR	mta-72-135-80-2.wi.rr.com
72.135.80.35	PTR	mta-72-135-80-35.wi.rr.com
72.135.80.98	PTR	mta-72-135-80-98.wi.rr.com
72.135.80.128	PTR	mta-72-135-80-128.wi.rr.com
72.135.80.131	PTR	mta-72-135-80-131.wi.rr.com
72.135.80.162	PTR	mta-72-135-80-162.wi.res.rr.com
72.135.80.163	PTR	mta-72-135-80-163.wi.rr.com
72.135.80.225	PTR	mta-72-135-80-225.wi.rr.com
72.135.85.0	PTR	mta-72-135-85-0.wi.rr.com
72.135.85.2	PTR	mta-72-135-85-2.wi.rr.com
72.135.85.3	PTR	mta-72-135-85-3.wi.rr.com
72.135.85.64	PTR	mta-72-135-85-64.wi.rr.com
72.135.85.96	PTR	mta-72-135-85-96.wi.rr.com
72.135.85.131	PTR	mta-72-135-85-131.wi.rr.com
72.135.85.163	PTR	mta-72-135-85-163.wi.rr.com
72.135.85.192	PTR	mta-72-135-85-192.wi.rr.com
72.135.85.193	PTR	mta-72-135-85-193.wi.rr.com
72.135.85.195	PTR	mta-72-135-85-195.wi.rr.com
72.135.85.226	PTR	mta-72-135-85-226.wi.rr.com
72.135.93.129	PTR	mta-72-135-93-129.wi.rr.com