Complete six-piece set with sturdy storage box: includes six telescoping gauges organized for protection and easy transport. The hard case keeps gauges secure and simplifies storage between jobs. Durable chrome-plated construction: each gauge features a chrome-plated finish for corrosion resistance and long service life. The bright surface resists wear and simplifies cleaning. Wide measuring range: covers 5/16 inch to 6 inch (8 mm to 150 mm) to handle most common industrial and automotive internal measurements. Simple, reliable operation: insert the extended gauge into the hole or recess, release to let the head seat, lock the shaft, then measure the gauge diameter with a micrometer or caliper for an accurate reading. Consistent contact pressure: engineered with constant spring tension to maintain uniform contact during measurement, reducing variation and improving repeatability. Why you need this set: Saves time by providing the right size for a broad range of internal measurements in one kit. Protects measurement accuracy with spring tension design and solid construction. Portable and organized for technicians who move between shops, job sites, or vehicles. Key attributes at a glance: Function: internal bore and recess measurement using telescoping gauge transfer method Compatibility: read with any micrometer or caliper Size range: 5/16 in — 6 in (8 mm — 150 mm) Material/finish: chrome-plated for durability Performance: constant spring tension for consistent results Practical applications / use scenarios: 1. Automotive engine rebuilds — measure cylinder bores, valve guides, and bearing recesses to verify clearances and tolerances. 2. Machine shop quality checks — transfer internal dimensions of drilled holes, bores, and fittings to a micrometer for inspection and verification. 3. Equipment maintenance and repair — confirm internal diameters on pumps, housings, and couplings during assembly or troubleshooting. What sets this set apart: the combination of a full 8–150 mm range, chrome-plated durability, a protective storage case, and constant spring tension delivers dependable, repeatable internal measurements for professionals who require accurate transfer readings on the job.