Review on Hembisen Portable 4 Gas Monitor ,Professional 4-In-1 Detector Alarm: Oxygen(O2)/Hydrogen Sulfide(H2S)/Carbon Monoxide(CO)/Explosive Gas(EX) Sniffer Tester With 2500MAh Battery & Color Display(Black) by Kenneth Mills

Pros:LightweightAudible AlarmColor DisplayEasy to UseRechargeableSensitive SensorsCons:NoneWhat I received in the package:1 x HEMBISEN Portable 4-Gas Monitor Detector1 x Standard Gas Sensor Cover1 x Power Adapter1 x microUSB Charging Cable1 x Metal Storage Case1 x Product User GuideThis HEMBISEN Portable 4-Gas Monitor Detector product is roughly 3” x 2 1/4” x 5 3/4” and weighs approximately 8.1oz. The detector has highly sensitive sensors that can effectively detect dangerous levels of gases. The detector offers an audible beeping and voice warning when dangerous levels are detected. It comes with a 19-Page Product User Guide which is only in EN. I highly recommend you reviewed this before use.The device is stored in a cushioned metal case to secure the device and keep it as safe as possible from damage.In testing the device, I was limited to propane as that is all I had on hand.The device clearly detected dangerous levels of propane gas when I opened the valve in an enclosed space. I device gave an audible beeping, red light flash and a vocal warning. It clearly was able to detect gas levels over and under the minimum presets.The unit takes a couple minutes to boot up and become ready. A couple of nice features are the various data viewers that available. You are able to customize some of the settings to your liking. As well as, perform zero & concentration calibrations. I calibrated the device even though it came calibrated. Upon checking it was spot on. The detector has an alligator clip that can clip right on to your person to keep the safe and aware the entire time they are working in a confined space.Only downside is that it cannot distinguish between O2 & O3. So if you need that, this is not going to do it for you.Per the Product User Guide, the manufacturer offers a 1-Year Warranty on this product.I appreciate you taking the time to read this. I received this product in exchange for an honest review. All in all, this is a decent detector. As far as the price point, in researching I found it was on the higher end of the price when compared to competitors with similar products. Hope this information was helpful. [4 Stars]This product is made in China.