High-precision gauge block set: Includes standard blocks, parallels, and slip gauges for calibration and inspection tasks. Versatile size combinations: Covers essential dimensions with stackable and paired options for complex measurements. Premium hardened steel construction: Offers excellent wear resistance and corrosion protection for industrial use. Complies with ISO 3650 standards: Each block is finely machined for dimensional stability and repeatable accuracy. Widely used in professional : for caliper, micrometer, and CMM calibration, machining, and quality control.