|“I can't get over how small you are!”
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A Circuit Breaker helps to open doors in co-op mode, when pressed simultaneously with another Circuit Breaker located on the other side of a door. The Ping Tool's countdown function is useful for synchronizing the action with your partner. It is also used in Single player as a simple button to activate a object. A Circuit Breaker can be found at the start of 1950's testing to activate the power of the entrance and the lounge, as well as at the Abandonment Hatch in the Tartaros 09 Area.