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Each list lets has a button to add new value, which can also be multiple values (separated by spaces or commas), then a small Save button at the far right side.

Once the list is created you will need to define in the ad-source the domain targeting and set it as Allowed (AKA Include) or Disallowed (AKA Exclude)

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Geo Targeting

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Allowed and Disallowed lists for geographical locations by Coordinates or Zip Code.

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