B-Complex is unique, including Metafolin, Methylcobalamin Vitamin B12, and Intrinsic Factor in its formulation. 

Metafolin contains only the S isomer of 5-MTHF and has been shown to be the only form of folate to be able to cross the blood-brain barrier. 

Studies indicate that methylcobalamin, a coenzyme form of B12, may be better utilized and better retained in the body. 

Intrinsic factor is a protein produced by cells in the stomach lining and is needed for the intestines to absorb vitamin B12 efficiently