FIG. 1 is a perspective view showing our new design of the mouthpiece for a spirometer:

FIG. 2 is a front view of the mouthpiece for a spirometer of FIG. 1;

FIG. 3 is a rear view of the mouthpiece for a spirometer of FIG. 1;

FIG. 4 is a left side view of the mouthpiece for a spirometer of FIG. 1 showing a tab portion in an alternative position, the right side being a mirror image;

FIG. 5 is a left side view of the mouthpiece for a spirometer of FIG. 1, the right side being a mirror image thereof;

FIG. 6 is a top view of the mouthpiece for a spirometer of FIG. 1;

FIG. 7 is a bottom view of the mouthpiece for a spirometer of FIG. 1;

FIG. 8 is a cross-section view of the mouthpiece for a spirometer of FIG. 1, taken along lines 8—8 of FIG. 2;

FIG. 9 is a cross-section view of the mouthpiece for a spirometer of FIG. 1, taken along lines 9—9 of FIG. 2; and,

FIG. 10 is a cross-section view of the mouthpiece for a spirometer of FIG. 1, taken along lines 10—10 of FIG. 2.

The dashed lines are for illustrative purposes only and form no part of the claimed design.