In 1895, the APCO/Valve and Primer Corporation introduced the world to the company’s first automatic pump primers. The primers were so successful, they became the foundation for APCO’s rich heritage of innovation. The next engineering and manufacturing marvels were APCO’s Air Valves and full Check Valve product line, introduced in 1957. Today, the APCO brand is synonymous with specialty valves built to customer specifications up to 120” in diameter.