Exhaust Valve for a Mask

FIG. 1 is a front perspective view of an exhaust valve for a mask showing my new design;

FIG. 2 is a back perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a back view thereof;

FIG. 5 is a left side view thereof, the right side view being a mirror image;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is another perspective view thereof, shown in a used condition with a mask and attachment shown in broken lines; and,

FIG. 9 is another perspective view thereof, shown in a used condition with a mask shown in broken lines.

The additional portions of FIGS. 8 and 9 drawn in broken lines and dash-dot lines show environmental structure only and form no part of the claimed design.