This mug has a stainless steel shell that serves to insulate the contents, and at the bottom of the mug is a small propeller, that will vigorously stir the contents to incorporate sugar or other flavorings.
The whirring propeller is powered by two AAA batteries that fit into a very slim compartment on the bottom of the mug. The propeller is activated by a thumb-switch on the top of the handle.
Mug comes with a sealing top with a drinking spout that lets you carry the mug while walking or driving, and drink the contents without spilling it. A great surprise gift!