Technical Data:
Series: 368
Product type: Holtest Bore Micrometer
Measurement: Inside diameter
Two-point contact type: Small-hole models
Three-point contact type: Self-centering for stable measurement
Feature: Measures close to bottom of a blind hole
Three-point models over 6 mm / 0.28 in use titanium-coated measuring pins
Three-point models can measure deep holes with optional extension rod
Contact type: Three-point
Measuring range: 250 - 275 mm
Graduation: 0.005 mm
Accuracy: +/-6 um
Optional extension rod: 952623 (150 mm)

Dimensions:
Maximum measuring depth L2=161 mm
Overall/reference length L1=227 - 252 mm
Blind-hole reference L3=12.4 or below mm
Blind-hole reference L4=21.0 mm
Blind-hole reference L5=13.8 mm
External appearance varies by measuring range