Robtex

Up: 200.81.4.0/22
Can't show all results, try to descend to a more specific CIDR
Down left: 200.81.6.0/24
Down right: 200.81.7.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
200.81.6.49	PTR	customer-200-81-6-49.millicom.com.ar
200.81.6.49	A	estudio-leotta.com.ar
200.81.6.49	A	icomland.com
200.81.7.137	A+PTR	mail.gamisol.com.ar
200.81.7.228	PTR	srvlm.lequipemonteur.com.ar
200.81.7.252	PTR	mail.astori.com.ar