Fixed gas detection for point source hazards and perimeter protection in arduous duty and exposed locations. Poison resistant catalytic combustion sensors. Available with a choice of analogue output signals: - 4...20mA • 0.4...2V • 5...15Hz. Signal fix during calibration to prevent false alarms and the main circuit inside the sensor housing can be removed from the housing for maintenance purposes. Quick change plug-in pre-calibrated gas sensing module. Special versions are available with waterproof plug and socket connectors.