Robtex

Up: 66.18.8.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 66.18.12.0/23
Down right: 66.18.14.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
66.18.12.20	A	mail.mceweninc.com
66.18.12.25	A	smtp.lucernex.com
66.18.12.25	A	smtp.lucernex.net
66.18.12.25	A	lucernex.net
66.18.12.35	A	ironport06.strongport.com
66.18.12.35	A	mailserv06.strongport.com
66.18.12.38	A+PTR	zixc1s4.strongport.com
66.18.12.38	A	zixvpm.strongport.com
66.18.12.38	A	zix07.strongport.com
66.18.12.39	PTR	zixc8s4.strongport.com
66.18.12.39	A	zixvpm.pcoa.com
66.18.12.42	A+PTR	zixc2s4.strongport.com
66.18.12.42	A	zixc2.strongport.com
66.18.12.50	PTR	cobc1s4.strongport.com
66.18.12.50	A	antispam2.enfieldha.org
66.18.12.54	A	zixc7.strongport.com
66.18.12.56	A	zixc9.strongport.com
66.18.12.66	A	uh1.mailsomemail.com
66.18.12.73	A+PTR	uh2.mailsomemail.com
66.18.12.73	A	mailsomemail.com
66.18.12.74	PTR	a.uh2.mailsomemail.com
66.18.12.74	A	doreenfreedman.com
66.18.12.79	A	uh3.mailsomemail.com
66.18.12.84	A	e.uh3.mailsomemail.com
66.18.12.108	A+PTR	uh8.mailerxsdd.com
66.18.12.109	PTR	a.uh8.mailerxsdd.com
66.18.12.135	A	remodelbyce.com
66.18.12.152	A	ryandillongolf.com
66.18.12.155	PTR	static9b.bluelineservices.com
66.18.12.155	A	bluelinesupport.com
66.18.12.161	PTR	statica1.summitmidstream.com
66.18.12.162	PTR	statica2.summitmidstream.com
66.18.12.162	A	www.summitmidstream.com
66.18.12.183	PTR	staticb7.trulend.com
66.18.12.183	A	midamericamortgage.com
66.18.12.183	A	affinitylending.com
66.18.12.204	A	balance2.hadelegation.net
66.18.12.217	PTR	staticd9.fireflycom.net
66.18.12.217	A	www.fireflyeducate.com
66.18.12.217	A	fireflytrain.com
66.18.12.218	PTR	staticda.fireflycom.net
66.18.12.220	A	fireflycom.sg
66.18.12.222	A	ns1.fireflycom.net
66.18.12.228	A	prefproc.com
66.18.12.250	PTR	staticfa.e-renter.com
66.18.12.250	A	e-renter.ca
66.18.12.250	A	erenter.ca
66.18.12.251	A	e-renter.net
66.18.12.253	PTR	staticfd.e-renter.com
66.18.12.253	A	sustainableorganicsllc.com
66.18.13.2	PTR	rv42120d02.sprocketnetworks.com
66.18.13.2	A	sharethestar.net
66.18.13.2	A	mypoolroute.com
66.18.13.4	A	rodeoincoleman.com
66.18.13.20	PTR	rv42120d14.sprocketnetworks.com
66.18.13.20	A	smtp4.moncor.com
66.18.13.20	A	moncormortgagebank.com
66.18.13.24	A	moncorbank.com
66.18.13.24	A	moncormortgage.com
66.18.13.25	A	moncortaxrelief.com
66.18.13.29	A	mail.mortgage-machine.net
66.18.13.30	PTR	rv42120d1e.sprocketnetworks.com
66.18.13.30	A	mail.trulend.com
66.18.13.30	A	webmail.trulend.com
66.18.13.44	A	mx.expeditiongrc.com
66.18.13.44	A	mx.expgrc.com
66.18.13.50	PTR	rv42120d32.sprocketnetworks.com
66.18.13.50	A	libertyredhawksbasketball.org
66.18.13.50	A	jkipcms.com
66.18.13.100	PTR	rv42120d64.sprocketnetworks.com
66.18.13.100	A	barbhanson.com
66.18.13.101	PTR	rv42120d65.sprocketnetworks.com
66.18.13.101	A	cpigroupinc.com
66.18.13.101	A	protechscreens.com
66.18.13.102	PTR	rv42120d66.sprocketnetworks.com
66.18.13.103	PTR	rv42120d67.sprocketnetworks.com
66.18.13.107	PTR	rv42120d6b.sprocketnetworks.com
66.18.13.107	A	texasnetworksystems.net
66.18.13.107	A	texnetsys.net
66.18.13.114	A+PTR	e-renter.com
66.18.13.114	A	tenantscreeningcenter.com
66.18.13.114	A	rentercreditcheck.com
66.18.13.116	A	tenantcentral.com
66.18.13.117	PTR	rv42120d75.sprocketnetworks.com
66.18.13.117	A	camelsafari.com
66.18.13.117	A	camelschool.com
66.18.13.118	PTR	rv42120d76.sprocketnetworks.com
66.18.13.162	PTR	rv42120da2.sprocketnetworks.com
66.18.13.162	A	api.flushimg.net
66.18.13.195	PTR	rv42120dc3.sprocketnetworks.com
66.18.13.198	A	castor.prenova.com
66.18.13.243	PTR	spamblock.internetwerx.com
66.18.13.244	PTR	spamblock2.internetwerx.com
66.18.13.245	PTR	imail.internetwerx.com
66.18.13.245	A	roachlawgroup.com
66.18.13.245	A	therealuntouchables.com
66.18.13.246	PTR	rv42120df6.sprocketnetworks.com
66.18.14.22	A+PTR	mail1.inflectra.com
66.18.14.22	A	mail.kronodesk.net
66.18.14.22	A	mail.spiraservice.net
66.18.14.62	PTR	unallocated.dal23e.sprocketnetworks.com
66.18.14.62	A	eaifresh.com
66.18.14.108	A	mail.bus-air.com
66.18.14.110	PTR	unallocated.dal26e.sprocketnetworks.com
66.18.14.110	A	usateamcorp.com
66.18.14.113	PTR	unallocated.dal271.sprocketnetworks.com
66.18.14.113	A	www.usahc.com
66.18.14.113	A	usagiving.com
66.18.14.122	PTR	vhost1.mckinneyit.com
66.18.14.123	PTR	mckinneyit.com
66.18.14.123	A	pacs.gatewaydiagnostic.com
66.18.14.125	A	help.networkingresults.com
66.18.14.178	A	ss54.mailboxesmore.com
66.18.14.182	A+PTR	ss55.mailboxesmore.com
66.18.14.194	A+PTR	ss48.mailboxesmore.com
66.18.14.194	A	www.mailboxesmore.com
66.18.14.194	A	mailboxesmore.com
66.18.14.195	PTR	a.ss48.mailboxesmore.com
66.18.14.204	A	ss50.mailboxesmore.com
66.18.14.204	A	ss50.sertmail.com
66.18.14.209	A	ss51.mailboxesmore.com
66.18.14.209	A	inproes.vivaincentives.com
66.18.14.211	A+PTR	b.ss51.mailboxesmore.com
66.18.14.214	A	ss52.sertmail.com
66.18.14.219	A	ss53.mailboxesmore.com
66.18.14.219	A	ss53.sertmail.com
66.18.15.13	A+PTR	mon01.sprocketnetworks.com
66.18.15.14	PTR	ns102.sprocketdata.com
66.18.15.14	A	ns2.noobsguideforstayingalive.com
66.18.15.14	A	odie.sprocketnetworks.com
66.18.15.21	PTR	mail.linelogix.com
66.18.15.22	PTR	rv42120f16.sprocketnetworks.com
66.18.15.22	A	losetowinnow.com
66.18.15.22	A	weightlossnow100.com
66.18.15.23	PTR	rv42120f17.sprocketnetworks.com
66.18.15.23	A	losetowinnow.com
66.18.15.23	A	weightlossnow100.com
66.18.15.24	PTR	rv42120f18.sprocketnetworks.com
66.18.15.24	A	healthyandfitweightlossmall.com
66.18.15.24	A	bhnutritionmall.com
66.18.15.25	PTR	rv42120f19.sprocketnetworks.com
66.18.15.44	PTR	rv42120f2c.sprocketnetworks.com
66.18.15.44	A	allorchidsupplies.com
66.18.15.44	A	idawebservices.com
66.18.15.45	PTR	mail.idawebservices.com
66.18.15.50	PTR	seco.serverevo.com
66.18.15.51	PTR	vps105.serverevo.com
66.18.15.54	PTR	vps108.serverevo.com
66.18.15.76	PTR	noc2.rjmcs.com
66.18.15.76	A	ns1.sequiam.com
66.18.15.76	A	auth1.sequiam.com
66.18.15.86	A+PTR	hosting.ntegrated.net
66.18.15.86	A	petrao.com
66.18.15.86	A	lindaperkinsphotography.com
66.18.15.90	A	vali.sprocketnetworks.com
66.18.15.91	A	vsa1.netresusa.com
66.18.15.95	A	tech.netresusa.com
66.18.15.134	A	mail.ashleyautomation.com
66.18.15.139	A	mail.bsaauditor.com
66.18.15.146	A	deliverystats.quattro.co.za
66.18.15.146	A	db3.quattro.co.za
66.18.15.163	A	mail.altresnetworks.com
66.18.15.187	A	mineolamedicallab.com
66.18.15.188	A+PTR	dover.agillaire.com
66.18.15.199	A+PTR	rv42120fc7.static.sprocketnetworks.com
66.18.15.210	PTR	rv42120fd2.sprocketnetworks.com
66.18.15.210	A	phirephly.org
66.18.15.210	A	hawaiivirtualreality.com
66.18.15.211	PTR	rv42120fd3.sprocketnetworks.com
66.18.15.232	PTR	rv42120fe8.sprocketnetworks.com
66.18.15.255	PTR	rv42120fff.sprocketnetworks.com