Achieve unparalleled precision with this SPI Gage Block Set, featuring 10 rectangular steel blocks ranging from 0.105 to 1 inch. Engineered with an exceptional tolerance of just 0.000006 inches, these high-quality calibration tools are essential for dimensional measurement applications requiring extreme accuracy. Each block in this comprehensive set is manufactured to exacting standards and comes with NIST certification, ensuring reliability in your most critical measurement tasks. The rectangular design allows for easy stacking and wringing when creating custom measurement standards. Perfect for quality control departments, machine shops, and calibration laboratories where precision is paramount. These durable steel blocks maintain their dimensional stability over time, making them a worthwhile investment for professionals who demand consistent accuracy in their measurements.