The DPP546618DA is a Quick Calibration Hood accessory designed for use with SGX VQ600 Series pellistor gas sensor heads in fixed gas detection systems. Constructed from polypropylene, this hood provides a convenient means of supplying test gases to the VQ600 in the field for calibration and checking purposes. The assembly push-fits into the central gas access recess of the head and is designed to accommodate 6 mm ID or 1/4" flexible tubing. With nominal dimensions of 58.0 mm height and 68.58 mm width, the Quick Calibration Hood enables efficient field maintenance and verification of gas detection system performance without requiring removal of the sensor head from its installation.