The toughness of a material can be measured using a small specimen of that material. A typical testing machine uses a pendulum to strike the specimen and deform it. The height from which the pendulum fell, minus the height to which it rose after deforming the specimen, multiplied by the weight of the pendulum is a measure of the energy absorbed by the specimen as it was deformed during the impact with the pendulum. The Charpy and Izod impact tests are typical measures of toughness.