The Starrett 456AZ Gear Tooth Vernier Caliper has a 20-2" Diametral Pitch Range with .001" graduation. It is designed to measure in .001" or 0.02mm the thickness of gear teeth at the pitch line (the chordal thickness of the teeth) using the distance from the top of a tooth to the chord. For the same purpose, it can also be used for measuring hobs, form and thread tools and more. This gage can be independently adjusted by screws on the graduated bars. Includes Case.
Starrett 456 Series Gear Tooth Vernier Calipers