Ventilation Mask

FIG. 1 is a rear, right and top perspective view of a ventilation mask, showing our new design; FIG. 2 is a front, left, and bottom perspective view thereof; FIG. 3 is a front view thereof; FIG. 4 is a rear view thereof; FIG. 5 is a left side view thereof; FIG. 6 is a right side view thereof; FIG. 7 is a top plan view thereof; FIG. 8 is a bottom plan view thereof; FIG. 9 is an enlarged view of portion of FIG. 1 thereof; and, FIG. 10 is an enlarged view of portion of FIG. 2 thereof. The dot-dash broken lines depict the boundaries of the enlargements that form no part of the claimed design. The broken lines depict portions of the ventilation mask that form no part of the claimed design.