5/16 in. x 1/4 in. White Nylon Reducing Compression Union
5/16 in. x 1/4 in. White Nylon Reducing Compression Union
Sizes in This Series
White nylon reducing compression unions. Jump to another size or add it straight to your cart:
| Size | Part # | Price | Cart |
| 5/16 in. x 1/4 in. (this page) | 17078N | $3.99 | — |
| 3/8 in. x 1/4 in. | 17079N | $5.99 | Add to cart |
Overview
The Midland 17078N is a white nylon reducing union that steps a 5/16 in. compression tube down to a 1/4 in. compression tube in one fitting. The two ends use 1/2-24 compression nuts to grip soft nylon or poly tubing without solder or threading. The corrosion-resistant nylon body suits water and chemical lines where a non-metallic reducer is wanted.
Technical Specifications
| Part Number | 17078N |
| Connection 1 | 5/16 in. Compression |
| Connection 2 | 1/4 in. Compression |
| Fitting Type | Reducing Union |
| Thread Size | 1/2-24 |
| Color | White |
Materials of Construction
| Body | Nylon (white) |
| Compression Nuts | Nylon |
| Sleeves / Ferrules | Nylon |
Typical Applications
Use this reducer to connect a 5/16 in. tubing run to a 1/4 in. line, match a larger supply tube to a smaller pump port, or transition between two tube sizes in filtration and dosing plumbing. The nylon construction is favored on potable water, RO, and chemical-feed lines that need a corrosion-free joint.
Cross-Reference and Interchange
This 5/16 in. x 1/4 in. white nylon reducing union cross-references to this competitor and industry part number: 15-5-4N-0. Replacing it? Match both nominal tube sizes, the compression ends, and the rating, or send us your part number and we will confirm the interchange.
Sizing and Installation Resources
- Compression Fitting Sizing Chart
- Metering Pump Chemical Compatibility Chart
- Chemical Compatibility Chart for Fluid Handling
FAQ
Which end takes which tube?
The larger 5/16 in. end accepts 5/16 in. OD tube; the smaller end accepts 1/4 in. OD tube.
Do I need inserts?
For soft poly tubing, a stiffening insert on each side helps the ferrule seal without collapsing the tube.
Is this the same as a reducer adapter?
It is a tube-to-tube reducing union; both ends are compression, not threaded pipe.
How tight should the nuts be?
Hand-tight plus a short wrench turn. Avoid over-torquing nylon threads.
WARNING: This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.