The ornamental design for a removablecover for airmask, as shown and described.
FIG. 1 is a front, right side, perspective view of a removable cover for air mask showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top view thereof;
FIG. 7 is a bottom view thereof;
FIG. 8 is an exploded view thereof; and,
FIG. 9 is another exploded view showing the removable cover for air mask in a state of being installed on the front of a mask.
FIG. 8 is an exploded perspective view showing a state in which the filters on both sides are separated from the subject design. FIG. 9 is a reference view which shows the state of being installed on the front of the mask. The broken lines indicate portions of the article that form no part of the claimed design.