3M 55597, Hookit Paper D/F Disc 236U, 6 in x NH 6 Holes P320 C-weight, 7000119588 
3M 77143, Scotch-Brite Hookit 7447 Pro Disc, PO-HA, A/O Very Fine, 6 in x NH 6 HL, 7010292688 
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.
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