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SKU: 604-00100-4000
Stainless Bros O2 Sensor Bung SS304 Saddle Type (Round) - Cast
The Stainless Bros 604-00100-4000 SS304 Saddle Type O2 Sensor Bung is the best high-quality weld-in solution for adding oxygen sensor ports to custom exhaust systems, downpipes, or headers. This cast stainless steel round saddle bung provides precise 90-degree mounting, excellent weldability, and corrosion resistance for accurate AFR readings in high-temperature turbo, NA, or racing applications.
Key Features
- SS304 Cast Construction: Durable stainless steel with superior corrosion resistance and heat tolerance
- Saddle Type Design: Round saddle base for strong, leak-free welds on curved tubing
- Standard M18x1.5 Thread: Compatible with most wideband and narrowband O2 sensors
- Easy Welding: Thick cast body and saddle shape simplify alignment and welding
Specifications
| Specification | Detail |
|---|---|
| Part Number | 604-00100-4000 |
| Material | 304 Stainless Steel (Cast) |
| Thread Size | M18x1.5 |
| Type | Saddle (Round Base) |
| Mounting Angle | 90-Degree |
| Finish | Natural Stainless |
| Country of Origin | United States |
| Warranty | Limited |
Product Notes
- Single O2 sensor bung – weld-in design for custom exhaust fabrication
Installation Notes
- Estimated time: 20-40 minutes, moderate difficulty, requires TIG welding
- Cut hole in tubing, align saddle, TIG weld around base – ensure proper sensor orientation
This Part Fits
| Application | Notes |
|---|---|
| Universal | Custom Exhaust Systems, Downpipes, Headers |
| Common Uses | Wideband O2 Sensor Installation, Turbo Builds, Exhaust Fabrication |
Why Choose Stainless Bros?
- Specialist in high-quality stainless exhaust components and fittings
- Precision cast SS304 saddle bungs for strong, leak-free welds
- Trusted by fabricators for reliable performance in custom builds
Frequently Asked Questions
-
Q: Is this cast or welded?
A: Cast stainless steel saddle bung for superior strength and weldability. -
Q: What thread size?
A: Standard M18x1.5 – fits most Bosch, AEM, Innovate wideband sensors. -
Q: Can it be used for narrowband sensors?
A: Yes, compatible with both narrowband and wideband O2 sensors. -
Q: Is welding required?
A: Yes, saddle bung must be TIG welded to exhaust tubing.
Shipping & Handling
- Method: UPS/FedEx Ground
- Availability: In stock, ships same or next business day
- Packaging: Official Stainless Bros retail packaging
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