Robtex

Up: 193.39.32.0/19
Can't show all results, try to descend to a more specific CIDR
Down left: 193.39.48.0/21
Down right: 193.39.56.0/21

IP	Type	Hostname
193.39.51.2	PTR	test.telewest.co.uk
193.39.51.30	A+PTR	external.endeavour.co.uk
193.39.51.38	A+PTR	smtp-out2.endeavour.co.uk
193.39.51.44	A+PTR	exmta2.endeavour.co.uk
193.39.51.45	A+PTR	exmta1.endeavour.co.uk
193.39.51.68	PTR	web3.holidayspace.com