Dynabrade 95675 1/4" Male Plug with 1/4" NPT Male Thread 
Dynabrade 97566 1/4" Safety Coupler, Female 
Insize 4130-56, METRIC THREAD PLUG GAGE, M56x5.5, 6928640340222
$192.36
Supplied with Go and No-Go gages together.
Class 6H.
Standard ISO1502.
Supplied with manufacturer inspection certificate.
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