Features: Compact structure and light weight, portable to use and store, providing you a better using experience. Adopts high precision sensor for fast response (<2 second) and accuracy detection (±10%F.S.). High-definition LCD display for clear and easy reading, HT601 supports digital & bargraph display and HT601A supports bargraph display. Dual-way alarm including sound alarm and bargraph alarm for timely feedback on the results. Powered by 3 * AAA battery (NOT included), with low battery indication, long standby and easy for replacement. Gas detected (partial listing): Acetone, Acetylene, Alcohol, Ammonia, Benzene, Butane, Ethanol, Ethylene, Oxide, Gasoline, Hexane, Hydrogen, Methane, Naphtha, Natural Gas, Paint Thinners, Propane, Solvents, etc. Specifications: Model: HT601 / HT601A (Optional) Material: ABS Color: Black Power Supply: 3 * 1.5V AAA battery (NOT included) Range: HT601: 0~9999ppm/0.00~20.00%LEL HT601A: Bargraph Display Accuracy: ±10% FS (Methane) Sensitivity: <50ppm (Methane) Response Time: <2 sec Warm Up Time: Approx. 30 sec. Display: HT601: Digital & Bargraph HT601A: Bargraph Display Alarm Mode: Visible & Audible Auto/Manual Zero: HT601: Auto & Manual HT601A: Auto Unit Change: only HT601 support Ambient Temperature: only HT601 support Alarm ON/OFF: √ Auto Power OFF: √ Low Battery Indication: √ Flexible Probe: Approx. 43.5cm / 17.13in Item Size: Approx. 15.3*5.8*3cm / 6.02*2.28*1.18in Item Weight: Approx. 235g / 8.29oz Package Size: Approx. 28*11.5*4.5cm / 11.02*4.53*1.77in Package Weight: Approx. 381g / 13.44oz Packing List: 1 * Gas Analyzer 1 * Storage Pouch 1 * User Manual (English)