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Click on the relevant ad type
Select ‘Add/ Edit Placements’
Choose the wanted Placement, and click Edit
Under the Provider Placement Configuration, open 'GAM'Press press on '+Add Slot Level Targeting'
Add the Key and value
You can choose whether you would like the value to be Dynamic or Predefined.
Multiple KVs can be sent out by clicking on the '+Add Page Level Targeting'
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