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1PCS MQ-3 MQ3 Alcohol Ethanol Sensor Breath Gas Detector Ethanol Detection #F5

GD-3000 Flammable Gas-Leak Detector Gas Detector Sensor ✦KD #A6-42

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8CH Follow Sensor Module 8 Channel Tracking IR Infrared Detector for #F23

1PCS MQ-3 MQ3 Alcohol Ethanol Sensor Breath Gas Detector Ethanol Detection #A6-3