Properly flaring copper tubing is essential for creating secure, leak-free connections in plumbing and HVAC systems. Using the correct tube nut ensures a tight seal and prevents costly issues down the line. This guide will help you select the best tool for your needs.
- Precise Fit and Multipurpose: Secure 10 steel tube nuts with 3/16" tube diameter and (M10x1.0 Inverted) thread diameter (LTN31), ensuring effortless installation and a snug fit for a variety of applications.
- Versatile Compatibility: These brake line fittings adapt seamlessly to materials like steel, copper-nickel, copper-coated steel, PVF-coated steel, and stainless steel lines, providing unmatched versatility for your projects.
- Long-Lasting Durability: Plated to resist rust, our brake line tube nuts maintain their integrity in storage or high-moisture conditions, ensuring prolonged use. Backed by a lifetime guarantee, these fittings exemplify our commitment to quality and...
- Always Available Support: With 4Lifetime, you're never alone. Our dedicated customer service team is ready to assist you with any urgent issues, ensuring you're covered in the garage or on the road.
- VALUE PACK: This 100 Pcs Fittings kit for 3/16” & 1/4" Brake Line: 40 x 3/16" (3/8-24) Inverted Tube Nut; 6 x 3/16” (7/16-24) Inverted Tube Nut; 4 x 3/16” (1/2-20) Inverted Tube Nut; 4 x 3/16"(9/16-18) Inverted Tube Nut;4 x 3/16" (3/8-24) Inverted...
- PREMIUM MATERIAL: These brake line fittings are made from high-quality material to prevent rust and are plated for enhanced corrosion resistance, offering high ductility at high temperatures. The rear brake line inverted flare nuts and unions are durable...
- MULTIPLE SIZES: The unions and nuts have 4 sizes: 3/8-24 threads,7/16-24 threads, 1/2-20 threads, 9/16-18 threads (regular 3/16 & 1/4 inch tube fitting size). Match more application scenarios and meet your needs
- EASY TO INSTALL: Any 2 brake lines can be easily connected to the brake line adapter fittings. First, clean the surface of the brake pipe. Then, put nuts on each end of the two brake lines, and finally connect the two nuts with the brake line union...
- This component serves multiple functions such as connecting rods, pulling rods, or the top column, effectively acting as a nut for connecting or extending purposes. It has a wide range of remote-controlled cars and devices, including RC airplanes, FPV...
- Material: Carbon Steel; Color: Silver; Thread Size: M4; Thread Pitch: 0.7mm; Coupling Nut Size: 4.8x50mm / 0.19x1.97 Inch (Outer Diameter*Length); Thread Length of Each Side: 15mm / 0.59 inch
- Made of carbon steel material, smooth surface, with good appearance, and durable to use. Easy to use, no need for tools.
- Easy to install, each coupling nut can connect two thread pipes on both end. Or you can use screw on it.
- For 5/16" Tube
- 1/2-20 Threads (standard 5/16" tube fitting size)
- Standard Steel
- Most common SAE inverted flare sizes
- AN3 (3/8-24 UNF) stainless tube nut and sleeve assembly, fits 3/16" outside diameter hardline / tubing
- Package includes two nuts and two sleeves
- Manufactured from 304 stainless steel
- These stainless steel nuts and sleeves allow you to make a 37 degree flare -3 AN connection to the end of a 3/16 inch hard line tubing
- Thread Size: The thread size of 6an is 9/16-18 UNF,tube sleeve used to 3/8'' OD stainless steel tube.
- Material: Made of aluminum alloy 6061-T6, the working temperature range is from -65℉ to 252℉.
- Function: The nut is used for the conversion of the alloy pipe and the fitting,the sleeve is used to fix the pipe and prevent it from moving, and the sleeve is sealed with a 37 degree and an outer flaring of the pipe.
- Installation：Need to install the tube nut and sleeve on the tubing first.Then use a 37° flaring tool to flare the end of the coiled aluminum / stainless steel tube.Professional installation recommended.
- Item Package Dimensions:5.2 cm L X7.3 cm W X12.5 cm H
- Item Package Weight:0.077 Kilograms
- Country Of Origin: United States
- Product Type: Auto Accessory
- For 3/8" Tube
- 5/8-18 Threads (standard 3/8" tube fitting size)
- Standard Steel
- Most common SAE inverted flare sizes
- Item Package Dimension: 4L x 2.1W x 0.8H inches
- Item Package Weight - 0.05 Pounds
- Item Package Quantity - 1
- Product Type - NUTS
- Fitting Attachment 1: Female threads
- Fitting Material: Aluminum
- Fitting Size: -4AN, Finish: Black
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Last update on 2026-10-15 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Tube Nuts
Material and Durability
Tube nuts are typically made from brass or steel. Brass offers excellent corrosion resistance, making it ideal for water lines, while steel provides superior strength and is often preferred for higher-pressure applications like refrigeration lines. Consider the environment where the tubing will be used to determine the most suitable material.
Compatibility and Size
Ensure the tube nut matches the diameter of the tubing you are working with. Common sizes range from 1/4 inch to 7/8 inch in diameter. Check the specifications of your project or existing fittings to confirm the correct size. Some tube nuts are designed for specific types of tubing, so verify compatibility before purchasing.
Ease of Use and Type
There are several types of tube nuts, including standard flare nuts and compression fittings. Flare nuts require a separate flaring tool to create a cone shape on the end of the tube, which is then secured by the nut. Compression fittings use a ferrule that seals against the tube and fitting body when the nut is tightened, often requiring less specialized tools. Choose based on your experience level and the requirements of the job.
