Best Adapter Tube Nuts in 2026

Type: Compression Union

Tube Size:3/8" OD

Materies: BRASS

Fit for: the unions measures approx. 0.6 x 0.9 inch, the nut measures approx. 0.67 x 3/8 inch, fit for most common inverted flare or double flare sizes for 3/16 inch tube, for use with 3/16 inch steel, poly coated or copper brake lines; Please confirm the size of the details according to the picture before purchasing

Size and material: both the unions and nuts are metric 3/8-24 threads (regular 3/16 inch tube fitting size), all brake line fittings are made of quality brass to prevent rust and plated for corrosion resistance

You will get: 12 pieces brake line fittings in the package, include 4 pieces unions and 8 pieces nuts, you can share them with your family and friends, these tubes unions are good fittings

Most common SAE inverted flare sizes

Steel Brake Line Tube Nuts for 3/16" Steel Brake Line Tubing Inverted Flare Standard 3/8"-24 thread

SAE 3/16 tube size x 3/8-24 thread size

Hex plug with SAE 45-degree flare male end terminates tube size fitting

Brass for corrosion resistance, ductility at high temperatures, and low magnetic permeability

For use with LP and natural gas, refrigeration, and hydraulic applications

Includes 10 Steel Tube Nut, 3/16, M10x1.0 Inverted, per bag

Our brake line tube nuts are made with unmatched superior quality

Plated for corrosion resistance

★ 【Material】: Heavy Duty Brass,strong and durable. Dual couplings for joining two tubes of the same diameter(OD: Outer Diameter).

★ 【Firm And Durable】: Litorange Brass for corrosion resistance, high temperature ductility and low magnetic permeability.

★ 【Function】: Union for connecting and disconnecting two tubes more easily than with a coupling

Three piece construction - nut, sleeve and body with attached insert

Use with copper, brass, aluminum, or plastic tubing

Standard fittings use short nuts

STRAIGHT EXTENSION COUPLING TRAP ADAPTER: Upgrade your home's plumbing with a heavy duty trap adapter

DURABLE POLYPROPYLENE: Durable extension coupling is made from polypropylene for long-lasting use

INCLUDES REDUCING WASHERS: Comes with reducing washers to ensure a perfect fit

★ 【Material】: Made of premium solid brass with a longer service life, stronger and more durable than iron and iron galvanized pipe fittings.

★ 【Advantage】: The positive nature of the connection with the flare on the tube clamped between the nut and the body makes for extreme dependability and safety.

★ 【Application】: LP and natural gas, flammable liquids (special order), instrumental, refrigeration. power steering, hydraulic and pneumatic systems.Not for use in potable Drinking water applications.

PACKAGE INCLUDE - MuHize upgraded Brake Line Fittings Replacement (Pack of 15): ① 5 x 3/8-24 threads unions; ② 10 x 3/8-24 threads nuts. Note：Both the unions and nuts are 3/8-24 threads (regular 3/16 inch tube fitting size). Please check before shopping!

INVERTED FLARE UNION- Any 2 (3/16 inch) brake lines can be easy to joined with Muhize unions. both the sizes for unions and nuts are both 3/8-24 threads, which is the regular fitting size for 3/16 inch tube.

HIGHER QUALITY - MuHize brake line fittings are made of durable brass with unique rust corrosion proofing technology.

Made of stainless steel 304, heavy duty, durable and corrosion resistant.

1/4" outer diameter tube

Fittings for connecting and extending stainless steel, copper, rigid and semi-rigid plastic tubing

PACKAGE INCLUDE - MuHize upgraded Brake Fittings Replacement (Pack of 15): ① 5 x 3/8-24 threads unions; ② 10 x 3/8-24 threads nuts. Note：Both the unions and nuts is 3/8-24 threads (regular 3/16 inch tube fitting size) . Please check before shopping!

INVERTED FLARE UNION- Any 2 (3/16 inch) brake lines can be easy to joined with Muhize unions. both the sizes for unions and nuts are both 3/8-24 threads, which is the regular brake fitting size for 3/16 inch tube.

HIGHER QUALITY - MuHize brake fittings are made of durable brass with unique rust corrosion proofing technology.

The product is 1-1/2 WHT Drain Tee

Easy and simple use kit

The product is manufactured in China

SIZE: 1/4” Flare x 1/4“ Flare

EASY TO INSTALL: no need to resort to other tools, convenient for connection and disassembly

DURABLE: High grade brass construction for corrosion resistance, high temperature ductility and low magnetic permeability

12 Piece 3/8 Inch-24 Threads Brake Line Fittings Assortment - for 3/16 Inch Tube (4 Unions, 8 Nuts)

These brake line fittings are made of durable brass to prevent rust and plated for corrosion resistance. Both the unions and nuts is metric 3/8-24 threads (regular 3/16 inch tube fitting size)

Intended for most common inverted flare/ double flare sizes for 3/16 inch tube, for use with 3/16 inch steel, poly coated or copper brake lines

Auto Supplies Direct 3/16" Standard Inverted Flare Tube Nuts Pack of (15) for Cars and Trucks

For Automotive Brake Line Systems, Works With Your Preferred 3/16" Brake Line Of Your Choice

Most Common 3/16" SAE Inverted Flare / Double Flare Size

★ 【Material】: Made of premium solid brass with a longer service life, stronger and more durable than iron and iron galvanized pipe fittings.

★ 【Firm And Durable】: Litorange Brass for corrosion resistance, high temperature ductility and low magnetic permeability.

★ 【Application】: LP and natural gas, flammable liquids (special order), instrumental, refrigeration. power steering, hydraulic and pneumatic systems.Not for use in potable Drinking water applications.

Auto Supplies Direct (70) Piece 3/16″ & 1/4″ Brake Line Fittings Kit (3/16″ and 1/4″ Tube Nuts, Unions, and Compression Fittings) for Cars and Trucks

Contains a (30) Piece 3/16″ Inverted Flare Brake Line Fittings Assortment, which Includes: (10) 3/16″ Short Tube Nuts, (10) 3/16″ Long Tube Nuts, and (10) 3/16″ Unions

Contains a (30) Piece 1/4″ Inverted Flare Brake Line Fittings Assortment, which Includes: (10) 1/4″ Short Tube Nuts, (10) 1/4″ Long Tube Nuts, and (10) 1/4″ Unions

[100% BRASS ADAPTER] - The AC pipe joint connectors are all made by heavy duty brass, sturdy, durable, corrosion resistant and anti-rust.

[SPECIFICATION] - Fit for copper pipe Diameter 1/4" (6.35mm).

[APPLICATION] - The AC pipe jointers are designed to connect two copper pipes without welding. The connection can be tightened with a wrench, sturdy and durable. This flare fittings can also be applied in fuel and gas systems, plumbing, refrigeration, and vacuum applications.

Most common SAE inverted flare sizes

Steel Brake Line Tube Nuts for 3/16" Steel Brake Line Tubing Inverted Flare Standard 3/8"-24 thread

SAE 3/16 tube size x 3/8-24 thread size

【Package Includes】: 10 PCS 3/8" Compression x 3/8" Compression Union with A Sealing Tape.

【Lead Free Brass】: Heath and environment friendly material. Made of Lead Free Brass. Lead free brass is for both potable and non-potable water.

【Superior Material】: The 100% heavy duty brass tube fitting is firmer than iron and iron galvanized products, more robust and durable than castings.

SIZE - 1/4" Tube OD x 1/4" Tube OD x 1/4" Tube OD, Compression Tube Fitting mainly consists of a fitting body with a 24 degree tapered hole, a ferrule with a sharp inner edge, and a nut for compression.

MATERIAL - Made of high-quality brass, with strong wear and corrosion resistance, high compressive strength, durability, low magnetic permeability and high temperature ductility.

Use - Suitable for oil, gas, water and other non-corrosive or corrosive pipeline systems, temperature and pressure resistance, good sealing and repeatability, no need for welding and flaring tools, easy disassembly, installation and maintenance, etc.

【PREMIUM MATERIAL】：Our push in fittings are made of high quality CA360 brass,Certified by DOT and Air Brake system Requirements,with corrosion resistance, high temperature ductility and low permeability. Great for long time use, dot air brake fitting pneumatic fittings type: 1/4"

【TYPICAL APPLICATION】：The air brake fittings assortment kit can be used with air systems, copper tubing in air lines brake systems, which is perfect for automotive car or truck repair,air operated seats, operating gauges, air horns, heater controls, industrial workshops, daily garden or lawn mower repair, towing machine hose connection and air brake connections .

【EASY TO BE INSTALLED】: Union connect two tube with same OD. All quick connect fittings can be sealed by pushing the tube firmly into the fittings and they are also simple to be removed from the tube.

[Thread Size] The thread size of 3an is 3/8-24 UNF,tube sleeve used to 3/16'' OD inch stainless steel tube.

[Installation] Need to install the tube nut on the tubing first,followed by this tube sleeve.Then use a 37° flaring tool to flare the end of the coiled aluminum tube.Professional installation recommended.

[Function] The nut is used for the conversion of the hard pipe and the fitting,the sleeve is used to fix the aluminum pipe and prevent it from moving, and the sleeve is sealed with a 37 degree and an outer flaring of the aluminum pipe.

Type: Standard 3/8" Tube OD (Compression) male to 3/8" Tube OD (Compression) male.Compression nuts and ferrules included.5pcs

Reducing adapter for different size tube pipes or fittings,Both fitting connects to tubing end.

Tube OD Compression Straight Coupling Adapter for converting Aluminum, Plastic, and Copper straight compression thread pipe Tubing.

AN6 (9/16x18 UNF) aluminum tube nut and sleeve assembly, suitable for 3/8" outside diameter hardline / tubing

Package includes two nuts and two sleeves

Manufactured from lightweight 6061-T6 billet aluminum; Anodized finish for strength, durability and anti-corrosion

JIC -3AN Dash Size 3 AN 3 SAE thread, 1/16" ID sleeve, for 3/16" O.D. tube, hex replacement auto parts

-3 AN, package with 1-Nut and 1-Sleeve

Manufacture from lightweight 6061 t6 cnc machined aluminum alloy

6 AN tube sleeves and AN 6 (9/16-18) female thread tube nuts

Made from lightweight 6061-t6 cnc machined billet aluminum alloy

Black Anodized Finish for Long Last, Strength and Durability

Material: Brass; External Thread: M14; Internal Thread: M12; Thread Pitch: 1mm; Height: 10mm / 0.39 inch; Packing List: 5 x Brass Thread Adapter

Advantage: The product is made of brass material, providing good durability and stability. Convenient to use, it can convert two different thread.

Instruction: All threads body is very easy to use, just thread it into a nut or thread pipe.

Material: All brake pipe fittings are made of high-quality brass to prevent rust and plated to prevent corrosion.

3/16" Brake Line Fittings: 15 Fittings for 3/16" Brake Line: 5 x 3/8-24 threads unions; 10 x metric 3/8-24 threads nuts.

Size: The threads are 3/8 inch with a thread pitch of 24.