3/8-24-2B / 3/8-24-2AQI375 is an inch quick-release ball joint with a 3/8-24-2B female socket and a 3/8-24-2A male stud. An outer stainless steel spring provides tool-free disconnect and reconnect operation. Pin diameter A = 0.187 in., housing flange F = 0.687 in., ball housing G = 0.875 in., journal J = 0.500 in., body length L = 0.750 in., overall length M = 1.750 in., height N = 1.375 in., body width P = 0.812 in.
The QI series uses a carbon steel 1045 housing, a carbon steel 1045 ball stud, a carbon steel 1020 shell, and a stainless steel spring. Silver or yellow zinc plating is standard. Suitable for throttle and brake linkages, agricultural implement controls, and compact assemblies where frequent linkage removal is part of normal operation. Stainless versions available for corrosive environments.
Stainless steel version available with ‘S’ prefix (e.g., SQI375). Left-hand thread version available by adding ‘LH’ suffix. Yellow zinc plating available on request. The QD series is the inner-spring alternative.
All available sizes in the QI Series Quick Disconnect Ball Joint – Outer Spring series. Can’t find your size? Contact us for custom dimensions.
| PART NO. | D1 | D2 | A | F | G | J | L | M | N | P |
|---|---|---|---|---|---|---|---|---|---|---|
| QI187 | 10-32-2B | 10-32-2A | 0.125 | 0.438 | 0.438 | 0.313 | 0.438 | 1.094 | 0.906 | 0.438 |
| QI250 | 1/4-28-2B | 1/4-28-2A | 0.125 | 0.469 | 0.562 | 0.375 | 0.562 | 1.250 | 0.969 | 0.531 |
| QI312 | 5/16-24-2B | 5/16-24-2A | 0.156 | 0.531 | 0.687 | 0.437 | 0.625 | 1.453 | 1.125 | 0.605 |
| QI375 | 3/8-24-2B | 3/8-24-2A | 0.187 | 0.687 | 0.875 | 0.500 | 0.750 | 1.750 | 1.375 | 0.812 |
| QI500 | 1/2-20-2B | 1/2-20-2A | 0.250 | 0.875 | 1.125 | 0.625 | 1.000 | 2.530 | 2.030 | 1.000 |
Material certifications verified. Composition confirmed by spectrometer before machining begins.
100% go/no-go gauge check on all threaded sections. Zero tolerance on dimensional non-conformance.
Static and dynamic load tests run on representative samples from each production batch.
CMM verification of critical dimensions — ball diameter, bore, thread pitch, and body length.
Visual and tactile inspection for burrs, scratches, surface cracks, and plating defects.
Misalignment angle and torque measured to confirm liner performance meets specification.
Hardness tests confirm proper heat treatment on chromoly steel bodies and bearing balls.
Full traceability from raw material heat number to finished part. COC and inspection reports available.
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The QI375 is an inch-series quick-release ball joint with a 3/8-24-2B female socket and a 3/8-24-2A male stud. An internal stainless steel spring lets you disconnect and reconnect it by hand, so it's commonly used on throttle and brake linkages, agricultural implement controls, and other compact assemblies that get taken apart and reassembled often.
The QI375's socket half holds an internal stainless steel spring against the ball stud. Pressing the stud in past the spring seats it, and pulling straight out releases it — no tools, snap rings, or cotter pins needed for routine disconnect/reconnect.
Pin diameter (A) is 0.187 in., housing flange (F) is 0.687 in., ball housing diameter (G) is 0.875 in., journal (J) is 0.500 in., body length (L) is 0.750 in., overall length (M) is 1.750 in., height (N) is 1.375 in., and body width (P) is 0.812 in. — check these against your linkage clearance before ordering.
The housing and ball stud are both carbon steel 1045, the shell is carbon steel 1020, and the internal spring is stainless steel. Silver or yellow zinc plating is applied as standard for corrosion resistance.
Yes. A fully stainless steel version is available with an 'S' prefix (SQI375) for corrosive environments, and a left-hand thread version is available by adding an 'LH' suffix. Yellow zinc plating can also be requested in place of the standard silver finish.
The QI375 belongs to the QI series, which has an internal-spring, compact-body design. The QD series is the external-body variant of the same quick-release concept — choose based on the housing style your linkage or bracket is designed around, and confirm with SYZ before ordering.
