Automatic: Baby milk bottle shaker is an automatic mixer for baby formula and breast milk, which can mix baby formula more evenly and let the formula fully dissolve in water, while saving the time and trouble of manual mixing. 3 Mixing Modes: Baby automatic milk shaker has 3 mixing modes to meet different needs. Automatic mixing effectively reduces foam, which can prevent flatulence, indigestion and prevent babies' intestines. Portable: Baby formula mixer has a built in 1200mAh rechargeable battery that works for up to ten days after charging. Delicate and compact, easy to carry. Compatible: Automatic baby bottle shaker can also mix other beverages such as coffee, fruity drinks, tea, etc. It is compatible with bottles from 50 to 75mm in diameter. Low Noise: Portable feeding bottle shake machine is made of environmentally friendly ABS safety material, and the sound when mixing is less than 40dB, so it won't wake up babies.