Metallographic examination of longitudibally-oriented fastener specimens produces a great deal of useful information about fastener quality. Indeed, metallography is an indispensable tool for evaluating fasteners. Examination can reveal the presence of cracks or other surface flaws which may or may not, be harmful depending upon their location and nature. Metallography also can detect features associated with the manufacturing process and characterize the strenght of the fastener. All this depends upon proper selection and application of metallographic procedures.