The ornamental design for a cummerbund for attachment to load bearing vest, as shown and described.
FIG. 1 is a perspective view of a cummerbund for attachment to load bearing vest showing my new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a right side elevation view thereof;
FIG. 4 is a rear elevation view thereof;
FIG. 5 is a left elevation view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines showing on the cummerbund for attachment to load bearing vest are understood to represent buckles, and are not part of the claimed design.