Part of a Circuit Breaker

FIG. 1 is a perspective view of a part of a circuit breaker, in accordance with a first embodiment, showing the new ornamental design;

FIG. 2 is a front view of the part of a circuit breaker of FIG. 1 , showing the new ornamental design;

FIG. 3 is a perspective view of a part of a circuit breaker, in accordance with a second embodiment, showing the new ornamental design;

FIG. 4 is a perspective view of a part of a circuit breaker, in accordance with a third embodiment, showing the new ornamental design;

FIG. 5 is a front view of the part of a circuit breaker of FIG. 4 , showing the new ornamental design;

FIG. 6 is a perspective view of a part of a circuit breaker, in accordance with a fourth embodiment, showing the new ornamental design; and,

FIG. 7 is a front view of the part of a circuit breaker of FIG. 6 , showing the new ornamental design.

The broken lines shown illustrate portions of the part of a circuit breaker that form no part of the claimed design.