The ornamental design for a surface configuration of a vent for a headrest, as shown and described.
This application is related to the following co-pending application, of the inventor, filed on even date herewith:
Application Ser. No. 29/199,313, entitled "surface configuration of a vehicle seat".
FIG. 1 is a front view of a surface configuration of a vent for a headrest according to my novel design; and,
FIG. 2 is an enlarged left perspective view of the surface configuration of a vent for a headrest according to my novel design, the right perspective view being mirror symmetrical.