Robtex

Up: 216.66.28.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 216.66.28.0/25
Down right: 216.66.28.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
216.66.28.25	A	ns1.mailzee.com
216.66.28.26	A	ns2.mailzee.com
216.66.28.35	A	rimail2.rightinternet.com
216.66.28.35	A	rimail1.rightinternet.com
216.66.28.35	A	rimail5.rightinternet.com
216.66.28.38	A	shrmrgv.org
216.66.28.38	A	soonerhr.org
216.66.28.40	A	mail.frankduclos.com
216.66.28.74	A	mail.e-triage.com
216.66.28.74	A	e-triage.com
216.66.28.82	PTR	iade013nsw01.blackmesh.com
216.66.28.136	PTR	iade000-n.blackmesh.com
216.66.28.229	A	reseller.rightinternet.com