A great introductory demonstration of thermal expansion, large enough to be seen in the back of the room. This bimetallic bar will bend dramatically when heated in a Bunsen burner due to the different thermal expansion rates of each metal used in the bar. Let students examine the bar and discover for themselves that the two different sides of the bar are different colors and infer that different metals are fused together. Bar has convenient insulated handle. Bar length is 20 cm, overall length is 30 cm.