This 0 to 100 PSI, liquid filled Vacuum gauge with diaphragm and flush port is intended to be used in tough service conditions where vibration or pulsation is present. It's liquid filled design makes it vibration and shock resistant, while it's all stainless steel construction makes it resilient against structural damage. This gauge helps to monitor for optimal function of equipment that is dependent on pressurized motive flow, such as the Alfa Laval Vortex Shear-Mixer. It should be inspected periodically and changed out as needed. You can be assured of the right parts in the right packaging with the right fit and instructions. For detailed service instructions please refer to your Vortex Shear-Mixer manual.