Open Box! Never Used! The SPI Bore Micrometer Internal ID Mic .275-.350” is a precision tool designed for measuring the internal diameter of holes with a size range of .275 to .350 inches. This micrometer, from the trusted brand SPI, features a mechanical reading system for accurate measurements. Its bore micrometer design makes it ideal for metalworking inspection and measurement tasks, specifically catering to machinists and industries demanding high-quality craftsmanship. This tool provides reliable and precise results for ensuring optimal quality control in various manufacturing processes.