Voltage Sensor Module 25V Heat Shrinks it means no key is

it means no key is pressed down

Light Sensitive Photoresistor LDR - 12mm

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Voltage Sensor Module 25V Heat Shrinks it means no key isVoltage Sensor Module 25V The Voltage Sensor Module 25V is a simple but very useful module that uses a potential divider to reduce an input voltage by a factor of 5. The Voltage Detection Sensor Module 25V allows you to use the analog input of a microcontroller to monitor voltages much higher than it capable of sensing. For example, with a 0 5V analog input range, you are able to measure a voltage up to 25V. The module also includes convenient screw