JBO Thread Plug Gauge - UNC Go-No/Go - Left Hand - 2B - 1 3/8 x 6 Face Mill Arbors - Anti-Vibration Ideal for enlarging existing holes

Ideal for enlarging existing holes or achieving a specified bore in a variety of metals and alloys

and quality inspectors quickly determine whether threaded components conform to exact metric standards

HSS‑E (M35 cobalt) durability: Enhanced wear resistance for longer tool life and consistent performance in demanding materials

10 mm size is built for repeatable precision in demanding applications

while the left-handed spiral flute provides effective swarf management for a steady

JBO Thread Plug Gauge - UNC Go-No/Go - Left Hand - 2B - 1 3/8 x 6 Face Mill Arbors - Anti-Vibration Ideal for enlarging existing holesThe JBO Thread Plug Gauge is a precision tool designed for testing internal UNC left hand threads in holes and threaded fittings. Built for manufacturers, automotive shops, aerospace facilities, and serious hobbyists, it provides fast, on the spot verification of thread conformity using a clear Go No Go result. Sized for 1 3 8 in. x 6 in. UNC left hand threads with 2B tolerance, this gauge helps ensure proper fit and reliable assembly. Go No Go