<p>2 × 250 mm/4 × 250 mm</p> <p>The IonPac® AS4A-SC anion-exchange column is designed for the fast analysis of inorganic anions in environmental waters. The AS4A-SC was introduced in 1984 and has been the preferred column for inorganic anions. The AS4A-SC is the specified column in U.S. EPA Method 300.0 (A). Dionex continues to make advancements in our column technology and introduced the AS14A column in 2000. The AS22 is the newest carbonate-based column recommended for fast analysis of inorganic anions.</p>