Used in immunological research to quantify complement protein 4 (C4) levels in rat samples, aiding in the study of immune system activation, inflammatory responses, and autoimmune diseases. The kit enables accurate measurement of C4 concentration in serum, plasma, or tissue homogenates, supporting research in conditions such as systemic lupus erythematosus, rheumatoid arthritis, and other complement-mediated disorders in rodent models. Its high sensitivity and specificity make it suitable for monitoring disease progression and evaluating therapeutic interventions targeting the complement pathway.