Compatibilities sets the optional parameter "compatibilities": Select only placements that are associated with these compatibilities. WEB and WEB_INTERSTITIAL refer to rendering either on desktop or on mobile devices for regular or interstitial ads respectively. APP and APP_INTERSTITIAL are for rendering in mobile apps. IN_STREAM_VIDEO refers to rendering in in-stream video ads developed with the VAST standard.
"APP" "APP_INTERSTITIAL" "IN_STREAM_VIDEO" "WEB" "WEB_INTERSTITIAL"