Back brace

FIG. 1 is a lower perspective view of a back brace, showing our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof; and,

FIG. 5 is a left side elevation view of the back brace in FIG. 1.

The broken lines shown herein are for illustrative purposes only and form no part of the claimed design. The right side elevation view for the embodiment of the back brace shown in FIG. 1 is a mirror image of the left side elevation view in FIG. 5.