Detection range: approximately 50 to 10, 000 ppm* (based on methane) Two levels of sensitivity: high (approximately 50 to 1000 ppm) and low (approximately 50 to 10, 000 ppm) Five red LED's (visual) and 85dB audible alerts that increase with gas concentration Automatic zero-point calibration at power-up (lights will flash during self-calibration; this does not indicate the presence of gas) 18-Inch flexible gooseneck expands sensor's reach; clips onto meter for storage, Weight: 0.8125 pounds, Manufacturer: Klein Tools