The FIT shaker is very unique with many added features. It is duo-sided that allows the user to actually blend and drink separate liquids from the same bottle. One side has a 22oz capacity, and the other is 14oz. It can be used with pre and post workout powders, protein powder, and is ideal for our FIT Ultimate Muscle Fuel, and our Fortifeye SuperFood. The lid features four snaps to secure the liquid or powder, and it has measuring markers printed on each compartment for easy filling. This is a very well constructed and heavy duty shaker. Hand wash only please.