Robtex

Up: 5.172.64.0/19
Can't show all results, try to descend to a more specific CIDR
Down left: 5.172.64.0/21
Down right: 5.172.72.0/21

IP	Type	Hostname
5.172.64.13	A	mail.phonethings.nl
5.172.64.242	PTR	ip-242-64-172-5-dyn-dsl.customer.digitelitalia.com
5.172.65.65	PTR	ip-65-65-172-5-dyn-dsl.customer.digitelitalia.com
5.172.65.146	PTR	ip-146-65-172-5-dyn-dsl.customer.digitelitalia.com
5.172.67.225	PTR	speedtest.digitelitalia.com
5.172.69.68	A	cuspide68.linkpc.net
5.172.71.71	A	mail.falchipaolo.it
5.172.75.3	PTR	ip-3-75-172-5-dyn-dsl.customer.digitelitalia.com
5.172.75.21	PTR	ip-21-75-172-5-dyn-dsl.customer.digitelitalia.com
5.172.76.2	PTR	ip-2-76-172-5-dyn-dsl.customer.digitelitalia.com