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

★ 【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

★ 【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.

Three piece construction - nut, sleeve and body with attached insert Use with copper, brass, aluminum, or plastic tubing

Manufactured for low and medium pressure tubing connection work where excessive vibration or tube movement is not involved.

Use with copper,aluminum and thermoplastic tub-ing.Not recommended for steel tubing.

Half union for connecting and disconnecting two tubes more easily than with a coupling

45-degree flare head tube connection on one side and a male NPT connection on the other

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

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.

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 (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

【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.

SIZE - 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.

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.

Package Qty : 1 Piece Fitting + 2 Nuts

Material : Copper

Size : 3/8"

Type: Female 45 Deg flare swivel nut union

Hose ID: 1/4"

Swivel Nut: 3/8" Female