When purchasing B12 you should always get Methylcobalamin rather than Cyanacobalamin.
MAX ABSORPTION, Vitamin B12 Sublingual Liquid Drops, 3000mcg Methylcobalamin Per Serving, 60 Servings, Non-GMO, Vegan Friendly
This is an excellent product that can be purchased at Amazon. It is a very good price for the quality and strength of the product.
B12 LIQUID METHYLCOBALAMIN 4 FL OZ 1 MG
This is 4 ounces of Methylcobalamin for about $5 per ounce. This is by far the best price and the strength is 5000 mcg. You are getting a large quantity of maximum strength B12 for a great price.