is not perfect, the place that shouldn’t be bought is not terrible. If my protein powder gets stuck in the lower corner first, shaking vigorously will only make the milk froth bigger. If protein powder is added after the water/milk, the protein powder will stick to the recessed cigarette holder lid. Now if you only use it to mix pre/bovine serum albumin/creatine powder, then you are rich, you can mix well, and you can drink in the gym without shooting a ball. I am very happy that it does not contain BPA and is made in the United States, but it has not replaced my pink blender bottle.