1. The Portable EX O2 H2S CO 4 In 1 Gas Detector ensures accurate readings with a precision of ≤±5%FS 2. This advanced 4 In 1 Gas Detector monitors multiple gases including EX (0-100)%LEL, H2S (0-100)ppm, CO (0-1000)ppm, and O2 (0-30)%vol 3. Equipped with low and high alarm settings for each gas, the 4 In 1 Gas Detector alerts you promptly to dangerous levels, with a low alarm at 20% LEL for EX and 10 ppm for H2S 4. Featuring an LCD display that shows real-time data and system status 5. Designed to operate in extreme conditions (-20℃ to 50℃) with an IP65 protection grade, Manufacturer: OUHFCASN