Sublingual B12 supplies the active Coenzyme form of Vitamin B12 used by your mitochondria: Adenosyl Cobalamin, along with the other Coenzyme form of Vitamin B12: Methyl Cobalamin.
We include a larger amount of the Adenosyl compared to the Methyl form because Methyl Cobalamin also methylates Mercury, which is a very common toxin that builds up in biological systems.
We do not use Cyanocobalamin, because it is not ready to be active as an enzyme cofactor in the body.
Keep it under your tongue as long as you can to maximize sublingual absorption. Then swallow for additional absorption in the distal ileum, the last part of your small intestine.