This meter is a combustible gas leakage detector, which is used to detect the leakage of combustible gas quickly and reliably. Features: FAST-RESPONSE GAS-SENSITIVE SEMICONDUCTOR SENSOR: Utilizing high-precision gas-sensitive semiconductor sensors, capable of measuring various combustible gases. HIGH/LOW SENSITIVITY SELECTION: Provides more precise detection of combustible gas leaks. AUDIBLE AND VISUAL ALARMS: Utilizes analog bars, red backlight, and audible alarms as triple warning methods. When a combustible gas leak is detected, the instrument emits a beep, the concentration analog bar increases, and the screen backlight changes from green to red. AUTO-POWER OFF: The instrument will automatically power off if there is no operation within 5 minutes. LCD DISPLAY SCREEN: In low-light conditions, the data is clearly visible, making it easy to monitor the current working status of the instrument. Specifications: Model: HT56 / HT56 Pro (Optional) Material: ABS Sensor: Gas-sensitive semi-conductor Range: 100~1000ppm Reactions Sensitivity: Approx. 1%LEL (100PPM)(methane) Display: LCD Automatic Power Off: Yes Low Battery Indication: Yes Dual Color Backlit: Yes Sensitivity Selection: Yes Buzzer Alert: Yes Warm-Up Time: Approx. 30 sec Response Time: ≤500PPM: Approx. 5 sec; 500PPM: Approx. 2sec Alarm Mode: Visible and audible Operating Conditions: 0~50 / 20~80%RH Storage Conditions: -10~60 / 20~80%RH Power Supply: 2 * 1.5V AAA battery (Not included) Safety Rating: EN61326-1 Item Size: 165 * 24 * 28mm / 6.49 * 0.94 * 1.10in Item Weight: 42g / 1.48oz Package Weight: 94g / 3.31oz Package Size: 20.5 * 6.5 * 4cm / 8.07 * 2.56 * 1.57in Package List: 1 * Pen-type Gas Leak Detector 1 * User Manual (English)