Dynabrade 95746 3/8" NPT Speed Regulator 
Insize 4131-5D2, AMERICAN STANDARD THREAD PLUG GAGE, 5/16-24UNF, 6928640358975
$87.51
Class 2B.
Standard ANSI/ASME B1.2
Supplied with Go and No-Go gages together
Supplied with manufacturer inspection certificate.
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