I like the electric shaker bottle - no batteries needed.

　　I doubt there is enough power to mix the protein. But this protein shaker bottle has been in use for a few weeks now with no complaints. Would buy again. Easy to use, comes with usb charger. I had a protein shaker that broke on a bus trip when I put it in my luggage.

　　Shaker Bottle makes protein shakes much easier to make. Not to mention very durable because I dropped it several times and it never stopped working.

　　I ordered this protein bottle in March and used it about 10 times to mix chocolate powder for chocolate milk. In mid-December, the electric blender bottle froze and stopped working, but still love it.