Description
Condition
Used (Like New).
This inside micrometer set is in exceptional, like-new condition. It appears to have seen very little to no active use. The micrometer head moves smoothly, the satin chrome finish is flawless, and the measuring faces on both the head and the extension rods are pristine. The screw threads on the extension rods—critical for accuracy—are clean and sharp. It comes complete in its original fitted case with the adjustment spanner and all extension rods present.
Product Overview
The Mitutoyo 137-102 (Series 137) is an Extension Rod Type Inside Micrometer, designed for the versatile measurement of internal diameters ranging from 50mm to 300mm. Unlike fixed-range micrometers, this “build-a-gauge” system allows you to cover a massive range of sizes using a single micrometer head and a series of interchangeable, hardened steel extension rods.
The set includes a main micrometer unit (with a 13mm travel) and multiple extension rods of varying lengths (13mm, 25mm, 50mm, 100mm, etc.). By combining these rods, you can achieve any dimension within the 50-300mm range. The measuring faces are hardened and ground to a radius to ensure proper contact with the bore wall. The scales are finished in satin chrome to reduce glare and prevent rust, making it an enduring standard for general workshop use.
Brand Information
Mitutoyo Corporation (est. 1934) is the global authority in precision metrology. The Series 137 “IMZ” micrometers are a staple in toolrooms worldwide because of their modularity. A single set replaces practically a dozen individual fixed micrometers, offering a cost-effective solution for maintenance shops and general machining where bore sizes vary wildly from job to job.
Specifications
| Feature | Specification |
| Model | 137-102 (IMZ-300) |
| Measuring Range | 50 – 300mm |
| Graduation | 0.01mm |
| Accuracy | ±(3 + n + L/50) µm* |
| Head Travel | 13mm |
| Rod Type | Solid Hardened Steel (Interchangeable) |
| Faces | Hardened, Radius Lapped |
| Included | Mic Head, 5 Rods, Case, Spanner |
*Note: Accuracy depends on how many rods (n) are connected and the total length (L).
Keywords
Mitutoyo, 137-102, inside micrometer, stick micrometer, extension rod micrometer, bore gauge, ID measurement, 50-300mm mic, machinist tools, precision measurement.
