Feature: 1. ACCURATE DETECTION: This module is capable of detecting smoke density and enables users to set a smoke detection threshold. When the smoke concentration exceeds the preset value, the relay closes, the alarm indicator lights up and the buzzer sounds an alert; when the smoke concentration falls below the threshold, the relay disconnects, the alarm light is off and the buzzer stops the alert. 2. ALARM FUNCTION: The sensor module triggers an alarm, relays, and indicator lights when the detected smoke concentration exceeds the set threshold. Conversely, the alarm, relay, and indicator lights cease when the smoke level drops below the threshold. 3. PRACTICAL FEATURES: The sensor module features a multi alert buzzer and offers relay switch output for enhanced alert notifications and response. 4. PROTECTION: The sensor module has reverse connection protection capabilities to prevent dangers associated with incorrect power supply connection. 5. WIDE APPLICATIONS: Our smoke sensor module is ideal for usage in public transport, public spaces, storage warehouses, and kitchens, providing safety and reassurance in areas susceptible to fires. Specification: Item Type: Smoke Sensor Module Switch Mode: MQ 2 Material: PVC Operating Voltage: DC5-30V Output Capacity: Control AC 220V 10A or DC 30V 10A or less equipment. Static Current: 20mA Dynamic Current: 50mA With anti reverse connection protection, the power supply will not burn the board. Service Life: More than 100,000 times, working temperature: -40 to 85℃ Positioning Holes: Spacing is Approx. 44mm / 1.73in long and Approx. 40mm / 1.57in wide, the aperture distance from the outer frame is Approx. 2.5mm / 0.1in, and the aperture is Approx. 3mm / 0.12in. . Package List: 1 x Smoke Sensor Module Switch