- Made in the U.S.A.
- Highly effective Caliper Attachment for quick, and accurate measurements of internal and external diameters of Retaining Ring grooves, O-Ring grooves and undercuts
- Available individually and in convenient sets
- Precision machined from steel, hard chrome plated for extra wear resistance
- Fits all 6" Vernier, Dial and Digital Caliper with a maximum jaw-thickness of .140"
- Measures internal grooves from .200" up to the capacity of the caliper