Manufacturer Part Number: 12X18X3-A2|Plate Type|2-LedgeGrade|AColor|BlackMaterial|GraniteThickness (Inch)|3Overall Length (Inch)|18Width (Decimal Inch - 4 Decimals)|12.0000Width (mm - 2 Decimals)|Includes|Two Accuracy CertificateStandards|ASME B89.3.7-2013; GGG-P-463c; ISO 17025; ISO 9001Thickness (mm)|Overall Unilateral Flatness Tolerance (mm)|Overall Length (mm)|Traceability Certification Included|NISTOverall Unilateral Flatness Tolerance (Decimal Inch)|0.000050UNSPSC Code|