【High Sensitive & Accurate Gas Sniffer】--Detect a variety of gases, Oxygen (O2), Carbon Monoxide (CO), Hydrogen Sulfide (H2S) and Explosive gas (EX). EX:0-100%LEL. O2:0-30%VOL. 【Practical Gas Sensor Detection Tool】--Compact size, easy to carry with a unique clip on the back side.
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