The product is a 4 3/8 8 STUB ACME 2G THREAD PLUG GAGE GO ONLY P.D. = 4.3375 manufactured by MERCURY GAGE. This thread gauge is specifically designed by PMC Group for metalworking inspection and measurement in CNC, metalworking, and manufacturing industries. The go-only feature indicates that it is used to check if the thread is within the specified tolerance, making it an essential tool for ensuring quality control in threaded components.
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