Digital Micrometer INSIZE 25–50 mm (model 3109-50A) — measuring range 25–50 mm

Digital micrometer INSIZE 25–50 mm (model 3109-50A) is a precision handheld instrument designed for accurate external dimensional measurement of shafts, rings and other small parts within the 25–50 mm range. The tool provides a clear digital readout for fast, unambiguous readings and incorporates a fine spindle control and hardened measuring faces to ensure repeatable contact and reduced wear during routine inspection tasks.

Advantages

The digital display enables immediate numerical reading with improved speed compared to analog scales. Fine spindle adjustment allows precise positioning and control of the measuring faces, while hardened anvils resist wear for enhanced long-term accuracy. The compact, ergonomic frame facilitates stable one-handed measurement in workshop and inspection environments. Metric graduations and a zero-setting function support typical quality-control workflows.

Suitable for

• External diameter measurement of shafts and pins
• Inspection of rings, collars and turned parts
• Workshop setups and maintenance checks
• Quality control and dimensional verification in manufacturing

Key specifications

• Measuring range: 25–50 mm
• Resolution: digital readout with fine resolution (typical for this class of micrometer)
• Measuring faces: hardened contact surfaces
• Spindle control: fine adjustment (ratchet or friction thimble style)
• Frame: compact, rigid C-frame for stability
• Display: digital LCD for clear numerical output

How to use

Before measuring, clean the workpiece and the micrometer measuring faces to remove dirt or debris. Close the micrometer gently on a reference gauge or the part using the fine spindle until stable contact is achieved, using the ratchet or friction thimble to avoid over-tightening. Read the value on the digital display and, if needed, use the zero-setting function to establish a reference. For repeated measurements, maintain consistent contact pressure and alignment of the part between the anvils to ensure comparability.

Usage recommendations

Store the micrometer in a protective case when not in use and avoid exposure to heavy shocks or extreme temperatures. Periodically check accuracy with a calibrated gauge block and replace batteries as needed to maintain reliable digital readout performance. Use the instrument on clean, room-temperature workpieces for best results.