MITUTOYO 611857-521 516 INDIVIDUAL METRIC GAGE BLOCK, RECTANGULAR SHAPE, 41.3 MM L, STEEL Precision gage blocks are the primary standards vital to dimensional quality control in the manufacture of parts Mitutoyo offers a complete selection of gage blocks available in a choice of rectangular or square, metric or inch and steel or CERA (ceramic) types If using only one length repeatedly, it is good practice to purchase discrete gage blocks Each gage block is supplied with a certificate of inspection Provided with inspection certificate These higher accuracy gages are intended for use within a controlled environment by skilled inspection staff Mainly used as reference standards for setting high-precision measuring equipment and for the calibration of lower grade gage blocks