What is claimed is the ornamental design for a circuit breaker, as shown and described.
FIG. 1 is a front top perspective view showing the circuit breaker of Applicant's new design;
FIG. 2 is a front bottom perspective view of the circuit breaker of FIG. 1;
FIG. 3 is a rear perspective view of the circuit breaker of FIG. 1;
FIG. 4 is a top plan view of the circuit breaker of FIG. 1;
FIG. 5 is a front elevation view of the circuit breaker of FIG. 1;
FIG. 6 is a right side elevation view of the circuit breaker of FIG. 1, the left side elevation view being a mirrored image of FIG. 6;
FIG. 7 is a bottom plan view of the circuit breaker of FIG. 1; and,
FIG. 8 is a rear elevation view of the circuit breaker of FIG. 1.
The broken lines in the drawings showing bolts, holes, and indicators illustrate portions of the circuit breaker that form no part of the claimed design.