A circuit breaker is a device that protects electrical circuits from damage caused by excessive current flow. This particular model, known as the Circuit Breaker Magnetic (Hydraulic Delay), has a high ampere rating of 20 A and can operate at both alternating current (AC) and direct current (DC) voltages of up to 480 V AC and 150 V DC respectively. It features a lever for manual operation and is designed for panel mounting.