This Finding Nemo thermal mug is metal on the outside and plastic on the inside. 

Please Note: Disney continuously changes the design of these thermal mugs, so often in fact, we cannot keep all the variations straight. With or without handle, with stainless trim, with no trim, with sunken lid, elevated lid, slide lock lid, flip top lid, turn bout spout lid, but the seagulls and the picture stay the same throughout. We apologize for any variations in the thermal mug you receive, as we are not allowed to object to this craziness!