Mask

FIG. 1 is a first perspective view of a mask showing the new design;

FIG. 2 is a second perspective view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a left side elevation view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof; and

FIG. 9 is a right side elevation cross-section view thereof taken along line 9 - 9 of FIG. 7 .

FIG. 10 is a first perspective view of another embodiment of a mask showing the new design;

FIG. 11 is a second perspective view thereof;

FIG. 12 is a front elevation view thereof;

FIG. 13 is a rear elevation view thereof;

FIG. 14 is a right side elevation view thereof;

FIG. 15 is a left side elevation view thereof;

FIG. 16 is a top plan view thereof;

FIG. 17 is a bottom plan view thereof; and

FIG. 18 is a right side elevation cross-section view thereof taken along line 18 - 18 of FIG. 16 .

FIG. 19 is a first perspective view of yet another embodiment of a mask showing the new design;

FIG. 20 is a second perspective view thereof;

FIG. 21 is a front elevation view thereof;

FIG. 22 is a rear elevation view thereof;

FIG. 23 is a right side elevation view thereof;

FIG. 24 is a left side elevation view thereof;

FIG. 25 is a top plan view thereof;

FIG. 26 is a bottom plan view thereof; and,

FIG. 27 is a right side elevation cross-section view thereof taken along line 27 - 27 of FIG. 25 .

The broken lines illustrate portions of the mask that form no part of the claimed design.