The sensor detects concentration of combustible gas: Methane, Propane and Carbon Monoxide in the air. Results can be obtained by measuring the voltage on the analog output. The system should be supplied with voltage from 2.5 V to 5 V. Thanks to built-in voltage converter, it is possible to use with 5V logic devices. Specification: - Supply voltage: 2.5V-5V - Outputs: analog, digital - Working temperature: -10 C - 45 C - 3mm Mounting holes - Dimensions: 31mm x 20mm x H 22mm https://elecena.pl/product/22624540/mq-9-carbon-monoxide-combustible-gas-sensor-arduino 2023-02-23 https://elecena.pl/product/22624540/mq-9-carbon-monoxide-combustible-gas-sensor-arduino 2025-10-28