The interchangeable rod depth micrometer is available as standard mechanical, mechanical digital and electronic digimatic (see separate digimatic entry). All models have hardened tool steel bases. Measuring rods are ground and micro-lapped on the faces. The sleeve and thimble are satin-chrome finished. Rod diameters are .157" (4mm) and are adjustable in either direction for calibration and wear compensation.

Accuracy: Rod diameter: 4mm.
Measuring length per rod: 1" (25mm).
Instrument error: ±3µm.
Flatness of reference face (bottom face of base):
1.3µm for 60mm/2.5" base. 2µm for 100mm/4" base.