... buttons7, highlight the Backlight8, precision: ≤ ± 5%1. Detection of gas: flammable gas2, detection principle: Electrochemical methods3, detection range: 0 ~ 100 ... % LEL,4, Resolution: 1ppm5, detection method: diffusion-type (can be added ... , metallurgy security ring, Chemical Services and other occasions Combustible Gas Detector