Starrett 99923 Steel Gage Block Set Grade B 81 Piece

Product Description

The STARRETT 99923 is an 81-piece rectangular steel gage block set built to Grade B accuracy for dimensional measurement and calibration work. Each block is individually serialized and ships with NVLAP Traceability Certification, making this set suitable for quality assurance environments where documented measurement standards are required. Tolerance is held to 50 microinches (0.00005 inches) across the full range. The set spans 0.05 to 4 inches in coverage, with step increments organized across four series to allow precise stacking combinations for a wide range of reference dimensions. Machinists, metrologists, toolroom technicians, and inspection personnel are the primary users.

This set is used in precision manufacturing, toolroom calibration, CMM setup, surface plate inspection, and machine tool verification. The four step-increment series included are: 49 blocks in 0.001-inch steps, 9 blocks in 0.0001-inch steps, 19 blocks in 0.050-inch steps, and 4 blocks in 1.000-inch steps. These series combine to cover a broad range of gage dimensions without requiring additional accessories. Grade B tolerance makes the set appropriate for general inspection and working-grade applications rather than laboratory master-block use.

Key Features

• 81 individual gage blocks covering 0.05 to 4 inches in total range
• Grade B accuracy with 50 microinch (0.00005 inches) tolerance
• Rectangular block form in steel construction
• NVLAP Traceability Certification included with the set
• Each block individually serialized for tracking and calibration records
• Four step-increment series for versatile stacking combinations

Compatibility

Designed as a working-grade gage block set for general toolroom, inspection, and dimensional calibration applications where Grade B rectangular steel blocks are specified.

Installation Notes

Gage blocks are precision measuring tools, not installed components. Handling should be done with clean, dry hands or lint-free gloves to prevent corrosion and contamination of lapped surfaces. Blocks should be wrung together on a clean, stable surface plate and separated carefully to avoid dropping or scoring the contact faces. Store blocks in the provided case when not in use to protect surfaces and maintain certification validity.