Accessory for a mask

[0001]FIG. 1 is a front view of an accessory for a mask showing my new design;

[0002]FIG. 2 is a rear view thereof;

[0003]FIG. 3 is a top view thereof;

[0004]FIG. 4 is a bottom view thereof;

[0005]FIG. 5 is a left side view thereof;

[0006]FIG. 6 is a right side view thereof; and,

[0007]FIG. 7 is a perspective view thereof.

[0008]The broken lines depict portions of the accessory for a mask that form no part of the claimed design.