3M 14308, AB14308, Square/Cross Pad Mandrel, 1/4 in 1/4-20 External, 7000045662 
Insize 3282-3, DISK MICROMETER, 2-3″, 6928640328107
$167.23
Graduation .0001″.
Measures root tangent length of gear.
Ratchet stop.
Supplied with setting standards (except with 0-1″).
Spindle lock.
Related products
Measuring/ Inspection Instruments
Insize 6140, DEPTH BASE ATTACHMENT, suitable for calipers with beam width (w) .630″, 6928640303579
$24.78