formaldehyde test,formaldehyde tester,formaldehyde inspector,formaldehyde monitor 24hour test formaldehyde easy using Household formaldehyde monitor BGFM ... electrochemical sensors and precision operational amplifier chip, uninterrupted change the interior formaldehyde concentration signals into electrical signals, ... 65mmWeight:220gUse scope:indoor , office , car formaldehyde tester inspector monitor