First fill a cup with about 200 ml of water or milk or your favorite drink and add a scoop of protein powder. Then start the electric cocktail shaker, it did not spill any water, I was surprised because the water kept spinning also formed a vortex, I repeated the spin twice. But you need to be careful if you add too much water you need to put the lid on to prevent splashing.
I also have a 45oz shaker, if I need to drink a lot I use the electric salt shaker to mix it well before pouring it in.
I do this because the best electric protein shaker mixes the drink better and tastes better than my hand shake.
VOLTRX Vortex Electric Protein Shaker Bottle (Red)Product on sale
Voltrx Vortex Electric Protein Shaker Bottle (Blue)Product on sale