Mitutoyo 389-371-30 Electronic Outside Micrometer IP65

Product Description

The MITUTOYO 389-371-30 is a deep-throat electronic outside micrometer designed for precise external dimensional measurement in demanding shop and field environments. With a maximum measurement range of 1 inch, a resolution of 0.000050 inches, and an accuracy of 0.000200 inches, this instrument delivers the fine measurement capability required for precision machining, inspection, and quality control work. The deep frame provides 6.3 inches of throat depth, allowing measurement access to workpiece features that standard-frame micrometers cannot reach. Carbide-tipped measuring faces resist wear during repeated use, and the IP65 rating provides protection against dust ingress and low-pressure water jets. It is used by machinists, metrologists, and precision trades professionals who require calibrated, reliable measurement tools.

The 389-371-30 is suited for precision measurement applications in manufacturing, tool and die, maintenance, and inspection environments where a deep-frame micrometer is required. Its electronic readout eliminates manual interpolation of thimble graduations, reducing reading errors during high-volume inspection or when working in low-visibility conditions. The ratchet stop thimble ensures consistent measuring force across repeated measurements, which is essential for maintaining accuracy and repeatability on tight-tolerance parts. The instrument ships with a plastic protective case for storage and transport, and includes one SR44 battery.

Key Features

• Deep throat frame with 6.3 inches of throat depth for measuring recessed or hard-to-reach features
• Electronic digital readout with 0.000050 inch resolution for high-precision measurement
• 0.000200 inch accuracy for tight-tolerance inspection work
• Carbide-tipped measuring faces for extended wear resistance
• IP65-rated for dust-tight and water-jet-resistant operation in shop environments
• Ratchet stop thimble ensures consistent and repeatable measuring force
• TVR Certified and includes plastic storage case and SR44 battery

Compatibility

Designed as a standalone precision measuring instrument for use in any application requiring external diameter or thickness measurement up to 1 inch with deep-frame access. Consult the manufacturers documentation to confirm suitability for specific inspection protocols or calibration standards in use at your facility.

Installation Notes

This instrument is handled and used by qualified machinists, metrologists, or inspection technicians. No installation is required, but the micrometer should be zeroed and verified against a known standard before use per standard metrology practice. Keep the measuring faces clean and free of chips or debris before contact with a workpiece. Store in the included plastic case when not in use to protect the measuring faces and electronic components.