Product Description Replacement Infrared Methane LEL sensor for the Ventis® Pro. The Methane IR sensor can be set for a measuring range of 0-5% by volume with a .01% by volume resolution, or a 0-100% by volume measuring range with a .1% by volume resolution. If the Methane IR sensor is set for a 0-5% by volume measuring range, the calibration gas concentration is 2.5% by volume methane. If the Methane IR sensor is set for a 0-100% by volume measuring range, the calibration gas concentration is 99% by volume methane. If this sensor is set for the 0-100% by volume measuring range and calibrated with 99% by volume methane, the calibrations must be done by hand as the Docking Stations are not intrinsically safe. This 4 series sensor is only available for the Ventis Pro 5, and can only be installed in location 2. (This sensor will not fit or work with Ventis MX4 or PRO 4 Gas Monitors)Has your CH4 IR sensor failed or has a measuring range that's all over the place? It might be time to replace it. Repair your Industrial Scientific Ventis Pro Multi-Gas monitor by purchasing a new genuine Industrial Scientific (CH4) Methane IR Sensor.Need some DIY help changing a sensor or just some friendly technical help with repairing your instrument? Call customer service at 1-800-949-7233.