Aseptically collected from abattoirs approved by USDA. Triple 0.1m filtered. Serum is virus, endotoxin, mycoplasma and bacteriophage screened, and selected for itís ability to support growth of a wide range of cells in culture. Plating efficiency and cloning efficiency tested. Hemoglobin content < 15 mg/dl. Endotoxin level <0.5 ng/ml. Shelf life: 5 years.