King Instrument Company started in 1983 with two manual lathes, a cut-off saw, two drill presses, and 1,200 square feet of rented space. The goal was singular: build the best rotameters ever made. Today, the company operates from a 46,000-square-foot facility in Garden Grove, California, where it manufactures 95% of the 6,000 components used in its products. This vertical integration includes producing its own borosilicate glass metering tubes, trademarked as Kinglass. The product line spans acrylic body rotameters for cost-sensitive OEM applications, stainless steel tube meters for high-pressure and corrosive environments, glass tube meters for precise visual flow indication, polysulfone meters for chemical resistance, and PVC meters for water and wastewater service. King Instrument operates an in-house calibration laboratory and performs NIST-traceable calibration in accordance with ISA RP 16.6. The company serves water treatment, chemical processing, food and beverage, pharmaceutical, and general industrial automation applications worldwide.