Robtex

Up: 81.76.64.0/21
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Down left: 81.76.64.0/23
Down right: 81.76.66.0/23

IP	Type	Hostname
81.76.64.67	PTR	user-514c4043.l3.c5.dsl.pol.co.uk
81.76.64.69	PTR	user-514c4045.l3.c5.dsl.pol.co.uk
81.76.65.77	PTR	user-514c414d.l3.c5.dsl.pol.co.uk
81.76.67.228	PTR	user-514c43e4.l3.c5.dsl.pol.co.uk