Robtex

Up: 139.193.216.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 139.193.216.0/23
Down right: 139.193.218.0/23

IP	Type	Hostname
139.193.216.243	PTR	fm-dyn-139-193-216-243.fast.net.id
139.193.217.11	PTR	fm-dyn-139-193-217-11.fast.net.id
139.193.217.38	PTR	fm-dyn-139-193-217-38.fast.net.id
139.193.218.217	PTR	fm-dyn-139-193-218-217.fast.net.id
139.193.219.228	PTR	fm-dyn-139-193-219-228.fast.net.id