McMaster-Carr logo
    Forward
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Print
    How can we improve?
    Comments
    E-mail address (if you would like a response)
    6 Products

    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 Metric Class 6H Thread Fit—These metric-threaded gauges are class 6H, which is comparable to the fit of those with Class 2B Unified Standard.
    For Thread Fit—Thread fit designates the tightness or looseness of mating threads.
    Thread
    Size
    Thread
    Type
    Pitch Dia. Tolerance,
    mm
    Hardness
    Material
    Features
    For Thread Fit
    Each
    Go/No-Go Gauges
    M4 × 0.7 mmMetric
    		-0.005 to 0.005Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock HandleMetric Class 6H
    		23585A1150000000
     
    Go/No-Go Gauges with Calibration Certificate Traceable to NIST
    M4 × 0.7 mmMetric
    		-0.005 to 0.005Rockwell C70Chrome-Plated Tool SteelDouble-Ended Taperlock HandleMetric Class 6H
    		3206A117000000
     

    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 Metric Class 6H Thread Fit—For metric threads, the higher the class number, the looser the fit. Class 6H is the metric 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
    M4 × 0.7 mmMetric
    		0" to 0.0003"Rockwell C70Chrome-Plated Tool SteelMetric Class 6H
    		7968N36000000
     
    Go Gauges with Accuracy Certificate Traceable to NIST
    M4 × 0.7 mmMetric
    		0" to 0.0003"Rockwell C70Chrome-Plated Tool SteelMetric Class 6H
    		7968N126000000
     
    No-Go Gauges
    M4 × 0.7 mmMetric
    		-0.0003" to 0"Rockwell C70Chrome-Plated Tool SteelMetric Class 6H
    		7968N8100000
     
    No-Go Gauges with Accuracy Certificate Traceable to NIST
    M4 × 0.7 mmMetric
    		-0.0003" to 0"Rockwell C70Chrome-Plated Tool SteelMetric Class 6H
    		7968N171000000
     
    back to top