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)