Catalog > Consumer Electronics > Kits > Various Kits Adjustable Gas Sensor Board Adjustable Gas Sensor Board HKD MQ135 GAS SENSOR MODULE ADJUSTABLE GAS SENSOR BOARD FOR DETECTING A WIDE RANGE OF GASES, INCLUDING NH3, NOX, ALCOHOL, BENZENE, SMOKE AND CO2. 39.65 ZAR inc for 1 Each 11 in Stock Add Specifications, Prices & Availability may change without notice. Images are for illustration purposes only. E&OE Specifications Main chip: LM393,MQ-135 gas sensorDual signal output (analog output, and TTL level output)with high sensitivity and good selectivity for Sulfide, benzene Department of steam, smoke and other harmful gasesWith signal output indicator instructionsSize : 36mm x 24mm x 25mm(L x W x H)