FIG. 1 is a perspective view of the flush valve advertising display showing my new design;

FIG. 2 is front elevational view thereof;

FIG. 3 is rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines shown in FIG. 1 are for illustrative purposes only and form no part of the claimed design.