Precision meets reliability with the SPI Rectangle Steel Gage Block. This 0.101" measurement standard comes in Grade AS-1, offering exceptional accuracy for your most demanding dimensional calibration needs. Each block is manufactured to exacting specifications, providing a reliable reference for calibrating measuring instruments in industrial and laboratory settings. The rectangular design allows for easy stacking and wringing when combined with other blocks in a set. This particular model includes NIST Certification, documenting traceability to national measurement standards—essential for quality control systems and regulatory compliance. Crafted from high-quality steel for durability and dimensional stability, this gage block maintains its accuracy through repeated use. Part #15-015-1 is an indispensable tool for metrologists, quality inspectors, and machinists who require absolute confidence in their measurements.