Hard Fuel Line

FIG. 1 is an isometric perspective view of a hard fuel line according to the claimed design. FIG. 2 is a front view of the hard fuel line. FIG. 3 is a rear view of the hard fuel line. FIG. 4 is a left side view of the hard fuel line. FIG. 5 is a right side view of the hard fuel line. FIG. 6 is a top view of the hard fuel line; and, FIG. 7 is a bottom view of the hard fuel line. The broken lines in the drawings illustrate portions of the hard fuel line that form no part of the claimed design.