Plug

FIG. 1 is a perspective view of a plug showing our new design; FIG. 2 is a perspective view from another angle thereof; FIG. 3 is a front view thereof; FIG. 4 is a rear view thereof; FIG. 5 is a left view thereof; FIG. 6 is a right view thereof; FIG. 7 is a top view thereof; and, FIG. 8 is bottom view thereof. The broken line depict portions of the article that form no part of the claimed design.