Charcoal stripped fetal bovine serum has been absorbed with activated carbon that removes non-polar material such as lipophilic (lipid-related) materials (virus, certain growth factors, hormones and cytokines) regardless of molecular weight but has little effect on salts, glucose, amino acids, etc.
This results in a serum that is more defined since lipid-like components that may impact research results are not in the culture system. These can be added at desired concentrations for improved ability to do lipophilic-related research.