1. Electric Switch Function
The ESC has a port for electric switch (Price doesn't include the switch button). You can connect your own switch button to the port " ON/OFF, LED(5V), GND".
If connect ON/OFF pin and GND pin, the ESC is off; disconnect them, the ESC is on.
2. Built-in Anti-Spark circuit.
Tips: For ESCs without anti-spark circuit, recommend to you use anti-spark switch: