This item arrived yesterday and I am very excited to be able to use it. During the meal, I shook the protein shake. It mixes well with the powder and has less lumps than when mixed in a mixing bottle. There is a comment or two comments that the lid is not fully opened, which is completely incorrect. The function of the cover is a bit like a car door, because it will stop in the middle, but if you push it a little, it will flip over 180 degrees. Also mentioned that the lid feels weak, I feel pretty good, but I can understand what they are talking about because the lid is not as strong as other vibrating bottles. It seemed okay, because I didn’t even notice any spills or leakage, even though the breakfast milkshake I had was much thicker than milk and protein powder. I really like the feel of this electric shaker bottle because it is stronger and more flexible than ordinary plastic bottles. I highly recommend this product as an alternative to classic products.