Digit Counter Outside Micrometer Range 3 in to 4 in Resolution 0.0001 in Accuracy +/-0.00021 in Long Form Calibration Certificate No Dimension Type Inch Included Certification Short Form Certificate of Inspection Traceable to NIST Jaw Depth 2.244 in Mechanical Display Type Digit Counter Operation Type Mechanical with Counter Resolution - Counter 0.001 in Thimble Type Ratchet Anvil Material Carbide Anvil Shape Flat Lock Nut Type Lock Nut Maximum Measurement - Inch 4 in