Individual Inch Individual Metric Rectangular Gage Block Series 516 Series 516 FEATURES Suffix Number for Selecting Standard and Certificate Provided ASME Grade Steel, CERAK -516**00 -521*0 -531*AS-1 -541*AS- 2 -551** provided with Inspection Certificate** provided with Calibration Certificate and Inspection CertificateExample: 611821-5210.1mm gage block in grade 00.We make custom length gage block length: 0.1-1000mm