4 in 1 Gas Detector LCD Display Compound Gas Measurement Detector Sound Light Vibration Alarm Data Record Combustible Gas Detector Specifications: Model: WT8812 Range: Combustible gas LEL: 0~100%LEL Oxygen O2: 0~30%VOL Hydrogen sulfide H2s: 0~100PPM CO: 0~1000PPM Resolution:  Combustible gas LEL: 0.1%LEL Oxygen O2: 0.1%VOL Hydrogen sulfide H2s: 0.1PPM CO: 1PPM Accuracy: ≤±5%FS Response Time (90%): Less than 30 seconds Indication Mode: LCD displays real-time data and system state, LED, sound, vibration indication alarm Storage Conditions: Temperature: -10~55℃; Humidity: <85%RH Operation Conditions: Temperature : -20~50℃; Humidity: <95%RH non-condensing Working Voltage: DC3.7V (Li battery capacity 1800mAh) Charging Time: 4h Standby Time: More than 8h on end (slightly change with working state) Material: ABS Item Size: 153 * 71 * 49 mm / 6.02 * 2.79 * 1.93 inch Item Weight: 219g / 7.72oz