An Electro Static Discharge protection device that is provided to protect sensitive electronics on a Printed Circuit Board (PCB) from inadvertent electrical discharge. The protective device is formed as an intervening structure between a contact surface and a PCB and utilizing the same ground as used by the PCB. When an electrical discharge occurs, the discharge is directed toward the PCB and directed to at least one ground point on the PCB so as to avoid damage to sensitive components.

Provided is a multi-pole molded case circuit breaker (MCCB) with an insulation barrier for a rotary pin, in which an insulation barrier is provided in a rotary pin for inter-phase power transmission to prevent dielectric breakdown. The multi-pole MCCB includes a shaft assembly having a movable contactor and having a plurality of rotary pin holes formed in a penetrating manner, a base assembly to which the shaft assembly is rotatably accommodated to be coupled, a switching mechanism coupled to an upper portion of the base assembly and rotating the shaft assembly, a plurality of rotary pins coupled to the plurality of rotary pin holes in a penetrating manner, and an insulation barrier formed of an insulating material and covering the plurality of rotary pins.