Robtex

Up: 66.64.48.0/20
Can't show all results, try to descend to a more specific CIDR
Down left: 66.64.56.0/22
Down right: 66.64.60.0/22
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
66.64.56.74	A	mail.dlflange.com
66.64.56.218	PTR	office.chcp.edu
66.64.56.250	PTR	mailhost1.tecenzymes.com
66.64.56.250	A	ourmail.tecenzymes.com
66.64.56.251	A	mail2.tecenzymes.com
66.64.56.251	A	mail1.tecenzymes.com
66.64.57.3	A+PTR	mail.specialkidscare.com
66.64.57.3	A	server.specialkidscare.com
66.64.57.11	PTR	generic.specialkidscare.com
66.64.57.34	PTR	mail.truewater.com
66.64.57.46	A+PTR	mail.finsyn.com
66.64.57.50	PTR	mail.thecolegroup.com
66.64.57.62	PTR	remote2.truewater.com
66.64.57.202	A	cal-clhoustonfamilylaw.com
66.64.57.254	A	mail.wellborecapital.com
66.64.58.5	A+PTR	barracuda.sqmenergy.com
66.64.58.20	PTR	mail.quantumgas.com
66.64.58.20	A	mail2.quantumgas.com
66.64.58.122	A	mail.houstondigital.com
66.64.58.130	A+PTR	mail.qesc.com
66.64.58.187	A	mail.fuller-realty.com
66.64.58.202	A+PTR	mail.texasindependent.com
66.64.58.228	PTR	s151074.trixbox.com
66.64.58.228	A	rock2email.com
66.64.58.244	A	brewer-escalante.com
66.64.58.244	A	www.brewer-eng.com
66.64.59.3	A	barracuda.orpp.com
66.64.59.4	A	mail.orpp.com
66.64.59.66	A	dns1.communityfamilycenters.net
66.64.59.66	A	mail.communityfamilycenters.net
66.64.59.115	A	linked-intech.com
66.64.59.155	A	postelerectiongroup.com
66.64.59.155	A	postelbuilding.com
66.64.59.170	A	mail.romarpipeandrail.com
66.64.59.170	A	internal.romarpipeandrail.com
66.64.59.194	A	proactivelegal.com
66.64.59.194	A	exchange.proactivelegalsolutions.com
66.64.59.194	A	exchange.proactivelegal.com
66.64.60.18	A+PTR	mail.designatwork.com
66.64.60.18	A	mail.myphotoswork.com
66.64.60.19	PTR	vpn.designatwork.com
66.64.60.19	A	mail2.myphotoswork.com
66.64.60.19	A	mail2.designatwork.com
66.64.60.54	A	mail.the-rose.org
66.64.60.54	A	mail.therose.org
66.64.60.66	A	mail.texasextrusion.com
66.64.60.84	A	smtp.targetinggroup.com
66.64.60.154	PTR	mail.peektraffic.com
66.64.60.154	A	mail.signalgp.com
66.64.60.154	A	flmail.teknotraffic.com
66.64.60.210	A+PTR	houston.frontier-consulting.com
66.64.60.243	A	mail.dennard-lascar.com
66.64.61.2	A	cagmdpa.com
66.64.61.2	A	cagmdpa-mp1.com
66.64.61.90	PTR	mail.beerslaw.net
66.64.61.90	PTR	mail.seven.analytical.com
66.64.61.90	A	mail.southernanalytical.com
66.64.61.91	A	mail.prodctr.com
66.64.61.92	A	www.prodctr.com
66.64.61.92	A	prodctr.com
66.64.61.99	A	turbomech.com
66.64.61.99	A	mail.turbomech.com
66.64.61.151	A	mail.usbiweb.com
66.64.62.3	PTR	www.horizontaltech.com
66.64.62.34	PTR	rww.cbl-law.com
66.64.62.34	PTR	smtp.cbl-law.com
66.64.62.66	A	mail2.montcooc.com
66.64.62.114	A	firewall.infodatinc.com
66.64.62.116	PTR	filter.infodatinc.com
66.64.62.116	A	*.infodatsolutions.net
66.64.62.116	A	mail.infodatinc.com
66.64.62.122	A+PTR	mail.parallinx.net
66.64.62.122	A	*.parallinx.net
66.64.62.122	A	parallinx.net
66.64.62.126	PTR	mail.pathfinderlld.com
66.64.62.131	PTR	mail.csiionline.com
66.64.62.150	A+PTR	mail.raveneaux.com
66.64.62.203	A	mx.osyka.com
66.64.62.204	A	mail.osyka.com
66.64.62.206	A	docushare.osyka.com
66.64.62.211	A	mail.rfblaw.net
66.64.63.2	A	*.taxaware.com
66.64.63.3	A	mail.ecorpusa.com
66.64.63.67	PTR	mail01.netedgesolutions.com
66.64.63.67	A	ns.netedgesolutions.com
66.64.63.67	A	netedge.solutions
66.64.63.68	PTR	mail01.netedgesolutions.com
66.64.63.71	A	netedgesolutions.com
66.64.63.77	A	netedgesolutions.com
66.64.63.77	A	ns02.netedgesolutions.com
66.64.63.132	A	plant-4d.com
66.64.63.132	A	ceausa.net
66.64.63.132	A	mail.ceausa.net
66.64.63.202	A	mail.heritageplanners.com
66.64.63.202	A	mail.heritagewealthmgmt.com
66.64.63.234	A	mail.bassoe.com