The 3/8" FPT flush spinweld fitting is the small but critical threaded connection used when an RV tank plumbing setup needs a clean flush-mount female port. CPI Part #82 gives you a 3/8" Female Pipe Thread connection in a flush spinweld style, making it a practical choice for tank builds, tank repairs, and replacement plumbing points where a threaded fitting is required.
Features & Specifications
- CPI 3/8" FPT flush spinweld fitting
- Female Pipe Thread (FPT) connection
- Flush-mount fitting style for low-profile tank installations
- Spinweld design for permanent installation into compatible plastic tanks
- Part #82 / SKU 82
- Useful for RV tank plumbing repairs, replacements, and custom builds
Why Choose This CPI 3/8" FPT Flush Spinweld Fitting?
When you need a small threaded tank connection, using the right fitting matters. This CPI flush spinweld fitting gives you a 3/8" Female Pipe Thread connection without a bulky raised profile, which helps when space is tight or when you want a cleaner finished tank surface. It is also a better choice than improvising with the wrong size fitting and ending up with leaks, poor thread engagement, or an awkward plumbing layout.
Compare CPI Flush Spinweld Fittings
Not sure which CPI tank fitting size is right for your project? Here is a quick comparison of nearby flush FPT options:
| Model | Thread Size | Style | Best For | View Details |
|---|---|---|---|---|
| CPI Part #82 | 3/8" FPT | Flush spinweld | Small threaded RV tank plumbing connections | Current Product |
| CPI Part #83-LL | 1/2" FPT | Flush fitting | Stepping up to a slightly larger threaded port | View Details |
| CPI Part #79LL | 3/4" FPT | Flush spinweld | Larger line connections that still need a flush profile | View Details |
| CPI Part #55M | 1-1/4" FPT | Flush spinweld with membrane | Bigger threaded tank connections with added sealing help | View Details |
Tip: Match the fitting to the thread size you actually need first, then choose flush vs. raised style based on your available clearance and tank layout.
Technical Specifications
- Brand: CPI
- Part Number: 82
- Connection Size: 3/8"
- Thread Type: FPT (Female Pipe Thread)
- Fitting Style: Flush spinweld fitting
- Application: RV tank plumbing connection point
- Weight: 0.1 lb
What's Included
- One CPI 3/8" FPT flush spinweld fitting
- No additional hardware or installation tools included unless otherwise noted
Compatible Models & Alternatives
If you are comparing sizes or building out a larger tank plumbing setup, these related CPI fittings are good next options:
- CPI 1/2" FPT Flush Fitting - Part #83-LL
- CPI 3/4" FPT Flush Spinweld Fitting - Part #79LL
- CPI 1-1/4" Flush FPT Spinweld Fitting w/Membrane - Part #55M
Frequently Asked Questions
What does FPT mean on this CPI fitting?
FPT stands for Female Pipe Thread. That means this fitting is designed to accept a matching male threaded plumbing connection.
What is a flush spinweld fitting?
A flush spinweld fitting is designed to be spin-welded into a compatible plastic tank so the fitting sits in a low-profile, flush-style position instead of standing proud like a raised fitting.
Is this the same as CPI Part #82?
Yes. This listing is for CPI Part #82, a 3/8" FPT flush spinweld fitting.
Can I use this if I need a larger threaded fitting?
No. If your plumbing layout needs a larger thread size, you should move up to the correct fitting size instead of forcing reducers into the wrong base fitting.
Does this fitting include installation tools?
No. This product is the fitting itself only unless otherwise noted. Spinweld installation requires the proper tooling and a compatible tank material.
Why Buy from Elkhart RV Parts?
We carry hard-to-find RV tank fittings and plumbing parts that are easy to misidentify when you are buying from generic listings. That makes it easier to get the right CPI part the first time instead of losing time on returns or rework.
Use our AI Live Chat to compare thread size, fitting style, and related options before you order.
Factory-Fresh OEM Parts — the same brands installed in new RVs straight from Elkhart. Genuine, name-brand components made to order — never generic, never outdated. Sourced directly from the original RV manufacturers for perfect fit and factory-level quality.