AST Enzymes - Serracor-NK - Circulatory and Respiratory Support - 150 VCapsSerracor NK Advanced Circulatory & Respiratory Support Support optimal cardiovascular and respiratory health with AST Enzymes Serracor NK. This powerful systemic enzyme formula combines serrapeptase, nattokinase, and a synergistic blend of proteolytic enzymes designed to promote healthy circulation, support respiratory function, and maintain the body's natural inflammatory response. Key Benefits Cardiovascular Health: Nattokinase and serrapeptase work