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Compression cap fittings are essential for managing fluid lines in various applications, from plumbing to pneumatic systems. Choosing the right fitting ensures leak-free connections and optimal performance. This guide will help you navigate the options to find the most suitable compression cap fittings for your needs.
Package Include: Brass 3/8-inch Comrpression Cap -10Pcs, and suitable Sealing Washer - 10Pcs.
Versatile: Suitable for 3/8'' Comp supply line, plumbing repairs, toilets faucets, Add-A-Tee valve, washing / heater / dishwasher / under kitchen sink valves, and other applications requiring compression fittings.
Special Remarks: It's a 3/8'' compression fitting, NOT 3/8'' NPT thread. Double check your needs, if you need 3/8 NPT, It doesn't meet your requirements. But If you need a 3/8 compression fitting (for sink shut-off valves), then these are perfect.
Easy Installation: Designed for a secure, leak-proof fit with compression fittings.
Durable Material: Made from Brass for long-lasting performance.
Package Include: Brass 1/4-inch Comrpression Cap -15Pcs, and suitable Sealing Washer - 15Pcs.
Versatile: Suitable for 1/4'' Comp supply line, plumbing repairs, toilets faucets, Add-A-Tee valve, washing / heater / dishwasher / under kitchen sink valves, and other applications requiring compression fittings.
Special Remarks: It's a 1/4'' compression fitting, NOT 1/4'' NPT thread. Double check your needs, if you need 1/4NPT, It doesn't meet your requirements. But If you need a 1/4'' compression fitting (for sink shut-off valves), then these are perfect.
Easy Installation: Designed for a secure, leak-proof fit with compression fittings.
Durable Material: Made from Brass for long-lasting performance.
Sufficient Quantity: you will receive 100 pcs 3/8 compression caps, providing sufficient quantity for you to seek to optimize cost ratio; This large quantity ensures that you are equipped even for larger projects or frequent needs, while also providing a...
Size Information: the compression caps come in a size of about 3/8 inches, offering a better fit for various applications; This size ensures a snug fit for a wide range of uses, eliminating any room for leaks; Products that are easy to install and remove...
Brass Material: experience the nice ductility and durability of the brass compression fittings; Made of quality brass material, their longevity even under strenuous usage conditions is a testament to their nice quality and robustness
Use with Washers: these compression caps are designed to be applied with washers for seamless functionality; The ease of usage serves as an advantage as you can conveniently execute your repair, installation or maintenance tasks without encountering...
Extensive Usability: with an array of applications, you can use these 3/8 inch caps in a variety of fields, from industrial and manufacturing pieces to some domestic fixes; Their wide usage capability makes them a go to solution for a host of compression...
These 1/2 inch brass blanking nut caps effectively seal pipes and valves and come with a sealing washer to prevent leaks in vertical, horizontal, or angled installations.
Made of high-quality brass with a smooth, flat surface, sturdy, durable, rustproof, resistant to corrosion. Its precision thread design ensures a secure connection.
The internal thread diameter is about 19mm and the external diameter is 25mm. TIP: Please check the size before ordering. The hex head design allows for easy installation and removal by hand or with a regular wrench.
The brass cap is compatible with a wide range of pipes and valves. Suitable for washing machines, dishwashers, radiators, and faucets.
Packaging: 2 PCS 1/2 Inch Brass Blanking Caps with 3 PCS Washers.
Sufficient in Amount: you will receive 20 pieces of 3/8 compression fittings, which are enough for your daily use and replacement needs; The brasses are in gold color, which look vintage and suitable for many places
Suitable Size: threaded cap fits pipes up to 3/8 inch outside diameter, please pay attention to read the size description which is universal and can fit most machines, can bring you much convenience in your daily life; Please note the size before buying
Quality Material: the gas line caps are made of quality brass material, which are strong and not easy to break, rust, or fade, so you can use them for a long time with confidence, do not need to change them often
Multi Functions: ring caps can be applied for connecting, terminating, controlling flow, and changing the direction of piping in many different industries, which are convenient and practical to use
Wide Range of Uses: the 3/8 compression cap is mainly applied for sealing joints and pipes, and widely applied in outdoor gardens, washing machines, air conditioners, water heaters, storage rooms, and so on
Package Content: The package includes 6 end pipe caps and 6 rubber washers gaskets to prevent leaks, ensuring a tight fit for air, water, or gas lines. Enough quantity to satisfy your use needs.Please check the size details to ensure it fit yours before...
Versatile Applications: Durable and high standard brass plug hex head end pipe caps. Our pipe caps are frequently utilized in irrigation, underground sprinkler systems, swimming pools, plumbing fixtures, and rainwater collection systems, among others.
Product Details: Size: Inner diameter 0.51in/13mm, outer 0.67in/17mm, height 0.35in/9mm. Our cap fits 1/4-inch NPT female pipe caps, designed for 1/4in closing the end of pipes or fittings.The cap BODY is larger than the thread size – please measure...
Easy to Use: Each pipe cap is designed with a hex head and internal thread, easy to close the end of the pipes, and it is easy to detach.
High-Quality Brass Construction: Brass construction for corrosion resistance and high strength, much better than stainless steel or plastic; Set with rubber gasket, provide strong seal without slipping
EXACT DIMENSIONS – READ BEFORE BUYING: Inner Diameter: 13mm/0.51in, Outer Diameter: 17mm/0.67in, Height: 9mm/0.35in. Fits 1/4" NPT male threads. The cap BODY is larger than the thread size – please measure your pipe's outer diameter before ordering to...
Introduction: The 40pcs compression caps with 9/16"-24 unef thread are suitable for the outer diameter 3/8 inch of pipes and can be used for gas garden water air hose lines.
Material: Brass. Low magnetic permeability, good ductility and plasticity at high temperatures, higher strength and hardness, able to withstand certain mechanical stress and wear, not easily corroded in humid environments, and not easily damaged during...
Craftsmanship: The 3/8" compression fittings are with fine manufacturing process, smooth surface without burrs, with good polishability and a beautiful golden appearance.
Easy to Use: These gas line caps are easy to assemble, without the need for welding, flaring, or deburring. They can be easily connected to other components through threaded connections, welding, crimping, etc. When it is necessary to replace them, the...
Application: The 3/8" water line cas are often used in fields such as machinery, automobiles, and ships, and can quickly and easily connect various pipelines such as air, water, fuel, oil, and inert gases, such as water heating pipes, automobile exhaust...
Prompt reply: If you have any questions about the compression caps, please feel free to contact us at any time. We will do our best to provide you with help and give you a satisfactory answer.
Package Include: Brass 3/8-inch Comrpression Cap -25Pcs, and suitable Sealing Washer - 25Pcs.
Versatile: Suitable for 3/8'' Comp supply line, plumbing repairs, toilets faucets, Add-A-Tee valve, washing / heater / dishwasher / under kitchen sink valves, and other applications requiring compression fittings.
Special Remarks: It's a 3/8'' compression fitting, NOT 3/8'' NPT thread. Double check your needs, if you need 3/8 NPT, It doesn't meet your requirements. But If you need a 3/8 compression fitting (for sink shut-off valves), then these are perfect.
Easy Installation: Designed for a secure, leak-proof fit with compression fittings.
Durable Material: Made from Brass for long-lasting performance.
Brass Pipe Caps : the package comes with 6 pieces of brass fittings in 6 different sizes, namely 1/4", 5/16", 3/8", 1/2", 5/8", 3/4", you can get 6 flared fittings in total, offering different sizes to meet your diverse needs
Nice Combination: the gas line cap set has a nice combination of proper sizes of flare fittings, which can provide a strong connection to your pipe, which will make your job done in an easy and right way
Easy to Use: you can use the flare cap fitting in need easily, just choose the appropriate size of the connector to use and end or close the pipe end, tighten it with a wrench to ensure it is firm, convenient to use
Sturdy Material: each cap for gas line is made of quality brass material, sturdy and reliable, as brass has high strength and corrosion resistance, long life and good performance; And the cap plays an important role when dealing with high water pressure...
Various Applications: our gas pipe cap can be widely applied for fuel, oil, air, propane, liquid petroleum and natural gas pipe connections, which is ideal for liquid hydraulic applications as well as domestic use, suitable for indoor, outdoor and wet...
Last update on 2026-08-30 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Compression Cap Fittings
Installation and Maintenance Tips
Proper installation is key to a reliable seal. Ensure the tube end is clean, cut squarely, and free of burrs. Slide the nut onto the tube, followed by the ferrule. Insert the tube into the fitting body, then tighten the nut onto the fitting body. Overtightening can damage the ferrule or tube, while undertightening will result in leaks. Periodically check for any signs of leakage, especially if system pressure or temperature fluctuates.
Frequently Asked Questions
What is the difference between a ferrule and a nut in a compression fitting?
The nut is the component you tighten, which forces the ferrule against the tube. The ferrule is the ring that deforms and creates the seal between the tube and the fitting body.
Can I reuse a compression cap fitting?
It is generally not recommended to reuse compression fittings, especially the ferrule. The ferrule deforms during the initial tightening to create a seal, and reusing it may compromise the integrity of the connection.
What type of tubing is compatible with compression fittings?
Compression fittings are designed for use with soft copper, aluminum, or plastic tubing. The tubing must have a consistent outer diameter and be rigid enough to support the ferrule's compression.
How do I determine the correct size fitting?
The size of a compression fitting refers to the outside diameter of the tubing or pipe it is designed to connect. Measure the outside diameter of your tubing to select the appropriately sized fitting.
Are plastic compression fittings suitable for gas lines?
Plastic compression fittings are typically not recommended for gas lines due to potential compatibility issues and lower pressure ratings. Brass or stainless steel fittings are usually preferred for gas applications.
What causes a compression fitting to leak?
Leaks can occur from undertightening, overtightening which deforms the ferrule or tube, using the wrong size fitting, or if the tubing surface is damaged or not properly prepared.
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