A Protein Shaker is a tool that people use to mix or blend the protein powder. Usually, they have a measuring scale on the side so people can mix your protein powder with the desired levels of water, milk or a milk alternative. Makers of protein shakes may say that their products help lower body fat or promote weight loss. But protein shakes aren't a magic way to lose weight. The shaker features a unique removable agitator attached to the inner lid, which helps blend the protein shake and avoid unpleasant, undissolved lumps of powder. Protein Shaker is very useful.