FIG. 1 is a perspective view of the oil can showing the viewing window and the top open; FIG. 2 is a top plan view of the oil can showing the top open; FIG. 3 is a side elevation view of the oil can showing the viewing window and the top open; FIG. 4 is a bottom plan view of the oil can showing the top open; FIG. 5 is a front elevation view of the oil can showing the top open; FIG. 6 is a rear elevation view of the oil can showing the top open; FIG. 7 is perspective view showing the side of the oil can opposite the side containing the viewing window and the top closed; and, FIG. 8 is a top plan view of the oil can showing the top closed.