Pipe Threaded Setting Plug Gauge, Dimension Type Inch, Gauge Type Go/No-Go (Plus/Minus), Handle Design Double End, Included Handle Taperlock, Thread Class 2A, Thread Size 1/4 In.-18, Thread Type NPSM, Tolerance Class X, Gauge Finish Uncoated, Gauge Material Tool Steel, Handle Color Blue, Handle Material Aluminum, Hardness RC 60-62, Included Certification Certificate of Accuracy with NIST Traceability, Pitch Diameter - Go Member 0.4903 in, Pitch Diameter - No-Go Member 0.4859 in