100-125mm 3.94-4.92" Three Point Internal Bore Micrometer - 3227 Series (Insize)

The Insize 3227 Series Internal 3-Point Bore Micrometer is built for accurate, repeatable internal measurements across a broad range of bores. With three contact points, carbide measuring faces, and a ratchet stop, this tool delivers dependable readings while resisting wear in challenging workshop conditions.

Designed for engineers, machinists, and hobbyists who need quick bore checks, the 3227 covers bores up to 300 mm with a 0.005 mm graduation. It comes with extension rods and two sets of interchangeable jaws to adapt to different measuring ranges, and an optional setting ring (code 6312) is available for precise baselining.

• Interchangeable jaw sets for flexible bore coverage: Two jaw configurations let you quickly switch measuring ranges, reducing setup time and keeping readings accurate across a broad spectrum of bore sizes.
• Carbide measuring faces for wear resistance: Carbide contact surfaces resist wear, helping maintain consistent accuracy over many measurements and a longer tool life.
• Ratchet stop with extension rods for consistent reach: The ratchet stop ensures uniform pressure for repeatable results, and the included extension rods expand access to deeper or larger bores up to 300 mm.

This bore micrometer supports efficient workflows by delivering stable, repeatable readings without constant re-zeroing. Its durable construction and versatile jaw and extension options make it a reliable companion for quality control, machining setup, and precision inspe ction across a wide range of internal diameters.