The ornamental design for a durag, as shown and described.
FIG. 1 is a front, top, right side isometric view of a durag;
FIG. 2 is a front, top, left side isometric view of the durag shown in FIG. 1;
FIG. 3 is a front view of the durag shown in FIG. 1;
FIG. 4 is a right side view of the durag shown in FIG. 1;
FIG. 5 is a rear view of the durag shown in FIG. 1;
FIG. 6 is a left side view of the durag shown in FIG. 1;
FIG. 7 is a top view of the durag shown in FIG. 1;
FIG. 8 is a bottom view of the durag shown in FIG. 1;
FIG. 9 is a front, top, left side isometric view of the durag shown in FIG. 1 being worn on the head of a person; and,
FIG. 10 is a rear, top, left side isometric view of the durag shown in FIG. 9.
The portions of the durag shown in broken lines with shorter segments depict stitching that form no part of the claimed design. The zig-zag broken lines along the surface of the durag depict stitching that forms no part of the claimed design. The partial human figure illustrated by dash-dot-dash broken lines assists to illustrate the claimed design in a position of use and forms no part of the claimed design.