FIG. 1 is a left side elevational view of a heel insert for a shoe sole showing my new design;

FIG. 2 is a right side elevational view;

FIG. 3 is a top plan view;

FIG. 4 is a rear elevational view;

FIG. 5 is a cross-sectional view taken on line 5--5 of FIG. 1; and

FIG. 6 is a cross-sectional view taken on line 6-6 of FIG. 1.

The broken line showing of the remaining portions of the shoe sole and upper is for illustrative purposes only and forms no part of the claimed design.