Dynabrade 97570 1/2" NPT Female Safety Coupler 
Insize 4131-41, AMERICAN STANDARD THREAD PLUG GAGE, 4-40UNC, 6928640358906
$97.05
Class 2B.
Standard ANSI/ASME B1.2
Supplied with Go and No-Go gages together
Supplied with manufacturer inspection certificate.
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