Sheath Knife

FIG. 1 is a front, bottom and right side perspective view of a sheath knife, showing our new design;

FIG. 2 is a right side view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a front view thereof; and,

FIG. 7 is a rear view thereof.

The features shown in broken lines depict environmental structure and form no part of the claimed design.