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    8 Products

    Threaded Plug Gauges

    Test if internal threads fall within tolerance. These plug gauges are often used in nuts and tapped holes to confirm thread fit. For precision and accuracy, they’re manufactured to tight tolerances.
    Threads are within tolerance if it’s easy to thread a go gauge but difficult to thread a no-go gauge more than two turns.
    Class X Gauge
    Image of Product. Front orientation. Plug Gauges. Threaded Plug Gauges.
    Go Gauge—Go gauges check the minimum hole diameter.
    No-Go Gauge—No-go gauges check the maximum hole diameter.
    Accuracy Certificate Traceable to NIST—Gauges with an accuracy certificate traceable to NIST include verification from the manufacturer that their thread sizes are within tolerance. The certificate is also known as a certificate of compliance or a short-form certification.
    For Class 2B Unified Standard Thread Fit—For inch threads, the higher the class number, the tighter the fit. Unified Standard Class 2B is standard and works for most applications.
    For Thread Fit—Thread fit designates the tightness or looseness of mating threads.
    Thread
    Size
    Thread
    Type
    Pitch Dia.
    Tolerance
    Hardness
    Material
    For Thread Fit
    Each
    Go Gauges
    0-80
    		UNF
    		0" to 0.0002"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B, Unified Standard Class 3B
    		0000000000000
     
    Go Gauges with Accuracy Certificate Traceable to NIST
    0-80
    		UNF
    		0" to 0.0002"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B, Unified Standard Class 3B
    		0000000000000
     
    No-Go Gauges
    0-80
    		UNF
    		-0.0002" to 0"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B
    		000000000000
    0-80
    		UNF
    		-0.0002" to 0"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 3B
    		000000000000
     
    No-Go Gauges with Accuracy Certificate Traceable to NIST
    0-80
    		UNF
    		-0.0002" to 0"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 2B
    		0000000000000
    0-80
    		UNF
    		-0.0002" to 0"Rockwell C70Chrome-Plated Tool SteelUnified Standard Class 3B
    		0000000000000
     

    Go/No-Go Threaded Plug Gauges with Handle

    Speed up thread tolerance checks—the handle on these gauges gives you a good grip to quickly thread and unthread go or no-go gauges. Use these gauges to make sure nuts, tapped holes, and other parts fall within tolerance. All are precisely manufactured to confirm thread fit. If the plug gauges wear down, you can insert new ones (not included) onto the taperlock handle.
    A part is within tolerance if it’s easy to thread the go gauge into the part but difficult to thread the no-go gauge more than two turns.
    Go/no-go gauges have both a go gauge on one end of the handle and a no-go gauge on the other to speed up tests. Go gauges check the minimum internal thread size. No-go gauges check the maximum internal thread size.
    Class X Gauge
    Image of Product. Double-Ended Taperlock Handle. Front orientation. Plug Gauges. Go/No-Go Threaded Plug Gauges with Handle.

    Double-Ended Taperlock

    Handle

    Calibration Certificate Traceable to NIST—Gauges with a calibration certificate traceable to NIST were calibrated in a lab. The certificate, sometimes called a test report or long-form certificate, details the tested measurements.
    For Class 2B Unified Standard Thread Fit—For inch threads, the higher the class number, the tighter the fit. Unified Standard Class 2B is standard and works for most applications.
    For Thread Fit—Thread fit designates the tightness or looseness of mating threads.
    Thread
    Size
    Thread
    Type
    Pitch Dia.
    Tolerance
    Hardness
    Material
    Features
    Choose a Thread Fit
    Each
    Go/No-Go Gauges
    0-80
    		UNF
    		-0.0002" to 0.0002"Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock Handle
    Unified Standard Class 2B
    ,
    Unified Standard Class 3B
    		000000000000000
     
    Go/No-Go Gauges with Calibration Certificate Traceable to NIST
    0-80
    		UNF
    		-0.0002" to 0.0002"Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock Handle
    Unified Standard Class 2B
    ,
    Unified Standard Class 3B
    		0000000000000
     
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