(2 x .5mL) Positive /Negative QC The Syphilis Health Check Control Set contains syphilis antibodies positive and negative controls diluted in pooled human serum which has been tested and found negative for anti-HIV, anti-HCV and HIV-1 antigen. *Contains 0.09% NaN3 and 0.3% ProClin 300. (Perishable item- Ships Mon- Wed only. Please select 2nd day air at check out- Item should be refrigerated upon receipt)