Robtex

Up: 195.42.240.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 195.42.240.0/23
Down right: 195.42.242.0/23

IP	Type	Hostname
195.42.240.10	PTR	static-mail-240-10.engines.dengage.net
195.42.240.12	PTR	static-mail-240-12.engines.dengage.net
195.42.240.16	PTR	static-mail-240-16.engines.dengage.net
195.42.241.1	A+PTR	e241-1.engines.dengage.com
195.42.241.2	PTR	e241-2.engines.dengage.com
195.42.241.7	A+PTR	e241-7.engines.dengage.com
195.42.241.10	PTR	e241-10.engines.dengage.com
195.42.241.11	PTR	e241-11.engines.dengage.com
195.42.241.12	PTR	static-mail-241-12.engines.dengage.net
195.42.241.16	PTR	static-mail-241-16.engines.dengage.net
195.42.241.19	A+PTR	e241-19.engines.dengage.com
195.42.241.21	PTR	static-mail-241-21.engines.dengage.net
195.42.241.28	PTR	static-mail-241-28.engines.dengage.net
195.42.241.42	PTR	static-mail-241-42.engines.dengage.net
195.42.241.44	PTR	static-mail-241-44.engines.dengage.net
195.42.242.1	PTR	static-mail-242-1.engines.dengage.net
195.42.242.2	A+PTR	e242-2.engines.dengage.com
195.42.242.3	PTR	e242-3.engines.dengage.com
195.42.242.9	PTR	static-mail-242-9.engines.dengage.net
195.42.242.10	A+PTR	e242-10.engines.dengage.com
195.42.242.11	PTR	e242-11.engines.dengage.com
195.42.242.12	PTR	static-mail-242-12.engines.dengage.net
195.42.242.15	PTR	static-mail-242-15.engines.dengage.net
195.42.242.17	PTR	static-mail-242-17.engines.dengage.net
195.42.242.20	PTR	static-mail-242-20.engines.dengage.net
195.42.242.21	PTR	e242-21.engines.dengage.com
195.42.243.11	PTR	static-mail-243-11.engines.dengage.net
195.42.243.12	PTR	static-mail-243-12.engines.dengage.net