The ASTM test block is made of aluminum. It is divided into two areas (A and B) by a groove.
It is intended for testing the display sensitivity of the testing equipment. In area A, the penetrant currently in use is applied, in area B the "fresh" penetrant is applied.
By this method a direct comparison is obtained if the batch currently still meets the desired quality and/or fulfills the desired display capability.
Delivery with statement of conformity.