Robtex

Up: 64.94.24.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 64.94.24.0/25
Down right: 64.94.24.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
64.94.24.20	A+PTR	mail4.activeapp.email.active.com
64.94.24.20	A	mail4.activeapp.psmessage.com
64.94.24.20	A	activeapp.psmessage.com
64.94.24.25	A+PTR	4.eteamz.email.active.com
64.94.24.26	A+PTR	5.eteamz.email.active.com
64.94.24.185	A+PTR	mail1.activenetwork-emails.com
64.94.24.185	A	activenetwork-emails.com
64.94.24.190	A	activeoutdoors-news.com
64.94.24.190	A	newsletters1.activeoutdoors-news.com
64.94.24.194	A	outdoors-news.com
64.94.24.194	A	newsletters1.outdoors-news.com
64.94.24.198	A	newsletters1.activeworksoutdoors.com
64.94.24.198	A	activeworksoutdoors.com
64.94.24.202	A	active-journey.com
64.94.24.202	A	newsletters1.active-journey.com
64.94.24.208	A	parks-news.com
64.94.24.208	A	newsletters1.parks-news.com
64.94.24.212	A	campingfeedback.com
64.94.24.212	A	newsletters1.campingfeedback.com
64.94.24.221	A+PTR	activesports1.email.active.com
64.94.24.221	A	activesports.psmessage.com
64.94.24.221	A	activesports1.psmessage.com
64.94.24.234	A+PTR	email.fish-and-hunt.com
64.94.24.234	A	fish-and-hunt.com
64.94.24.239	A	activeadvantage.psmessage.com
64.94.24.239	A	activeadvantage5.psmessage.com
64.94.24.240	A	activeadvantage2.psmessage.com
64.94.24.241	A	activeadvantage3.psmessage.com
64.94.24.242	A	activeadvantage4.psmessage.com
64.94.24.244	A+PTR	activeadvantage8.email.active.com
64.94.24.244	A	img.activeadvantage.psmessage.com
64.94.24.250	A	c.ns.pexicom.com
64.94.24.250	A	dns1.pexdm.com
64.94.24.250	A	ns5.active.com
64.94.24.251	A	ns6.active.com
64.94.24.251	A	dns2.pexdm.com
64.94.24.251	A	d.ns.pexicom.com