Achieve precision measurements with the SPI Rectangle Steel Gage Block. This 6-inch Grade AS-1 gage block is manufactured to exacting standards, making it an essential tool for dimensional calibration and inspection tasks. Each block comes with NIST Certification, ensuring its accuracy and reliability for professional applications. The rectangular steel construction provides durability and dimensional stability over time, critical for maintaining measurement integrity in industrial and laboratory settings. Part #15-091-2 is designed for use in calibration, layout, and machine setup applications where precision is paramount. This high-quality gage block serves as a reference standard for verifying measuring instruments and establishing accurate dimensions during quality control processes. The steel composition offers excellent wear resistance, making this a long-lasting addition to your measurement toolkit.