This ball floats on the surface of the water contained in the sight glass (level gauge) allowing for a quick reading of the water level in the boiler. This is a circular item with a diameter of 5.8 mm which will fit into a tube of 5.9 mm and above. One water level indicator sphere per purchase.
WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.