Pet Services is Unique ID 1549 in the IAB Audience Taxonomy 1.1, in the Purchase Intent* branch under Purchase Intent*. Trillboards emits it on the bid request as a segtax=4 segment, the code every IAB-compliant DSP already reads, so a buyer already running "Pet Services" elsewhere can point that strategy at DOOH screens without rewriting taxonomy. Over the most recent 30-day window the network logged 9 cohort observations tagged with this segment across 26,859 approved screens.
Trillboards inventory concentrates in Taxi Rideshare Tv, Convenience Store, Grocery. Taxi Rideshare Tv is the largest category at 12,601 approved screens, average floor $2.57 CPM. Those are network-wide venue counts; add a venue filter to the line item to hold delivery to the surfaces you want.
Buying one or two tiers up captures more of the network and less of the segment; buying this leaf does the reverse. The OpenRTB payload carries every level of the chain, so a single bid request can be targeted at Pet Services or at any node above it. Intent cohorts compress the consideration window. Lead with the offer and a clear call to action.