Terg-A-Zyme is a powdered detergent more aggressive than citronox. A protease enzyme detergent is specially effective in instances where soiled instruments have dried or are heat sterlized prior to cleaning, a step taken in some facilities as a precaution against infection transmission. When this process bakes blood and other soils onto the surface, soaking in Terg-A-Zyme assist in subsequent cleaning to ensure that corrosive dried-on blood is removed and abrasive cleaning is not required. SOLD INDIVIDUALLLY OR 9 BOXES PER CASE.