FIG. 1 is a perspective view, showing the new design for a test gas delivery device;
FIG. 2 is a left side view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a top view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is a rear side view thereof; and,
FIG. 7 is a front side view thereof.
The broken line showing forms no part of the claimed design.