Graduation: .001" 

Special features :

•  Anvil and spindle hardened and precision ground — micro-lap finish on measuring faces. 
•  Quick and easy zero adjustment. 
•  Every thousandth is numbered micro-fine for easy reading. 
•  Deluxe heat-insulator on satin chrome finished forged steel frame, tapered for hard to get at places.
•  Disc type anvil and spindle - simplifies measuring thicknesses of difficult, closely spaced sections, 
    ribs, keys, fins, cutting edges on forming tools, chordal thickness of gear teeth, etc.  
•  Positive locking clamp.
•  Large diameter, disc will enter inaccessible places such as narrow grooves, slots and recesses over .030” width.