Max Adapter Compression Fittings for Your Plumbing Needs
Can a simple coupling change the way you finish jobs and avoid callbacks?
You’re looking for dependable connections that fit common pipe sizes without hassle. At Installation Parts Supply, you can get 3/8 compression coupling parts that help sealing and alignment so installs stay clean and perform well under pressure.
These couplings suit many applications: sewer drainage, gravity flow lines, and quick repair work on iron, plastic, or steel pipe. Their built-in rubber sealing gasket design helps resist shear forces and assists with pipe alignment to create a tight, serviceable joint.
You’ll also value the documented specs such as temperature range, nominal diameter fit, and vibration guidance so you can plan the job and choose compatible valves and accessories quickly.
Shop confidently at Installation Parts Supply for authentic parts, fast shipping, and friendly support so you can get back to work with fewer surprises.
Your Source for Reliable Compression Connections at Installation Parts Supply
Why these fittings are a good choice for quick, leak-resistant hookups

Select components that offer dependable pipe alignment and a secure sealing gasket with no extra tools required. You get fast, serviceable connections that work well for under-sink hook-ups, appliance lines, and light sewer repair tasks.
In this range you’ll find options compatible with copper, plastic, and selected steel components. Materials like 304 series stainless and other stainless steel parts improve corrosion resistance in wet applications.
- With basic hand tools and proper torque guidance, you can assemble a tight mechanical seal.
- These serviceable joints can be taken apart for maintenance without soldering or gluing.
- Good for potable water, gravity flow, and many sewer drainage uses; avoid high-vibration or high-heat spots.
- Nationwide stock plus friendly support help you choose the right coupling and get parts quickly.
| Material | Best Applications | Key Feature |
|---|---|---|
| 304 series stainless | Potable water, light sewer | Strong corrosion resistance |
| Brass body | Fixture lines, appliances | Pliable, easier to install in cold conditions |
| Ductile iron / cast iron | Sewer repair and gravity flow lines | Durable in burial or heavy loads |
| Plastic (with insert) | Low-pressure lines | Lightweight, avoid shear forces |
Max Adapter Compression Fittings: Key Features, Specs, and Performance
Get clear, measurable specs so you can pick the right coupling for each job without guessing.
These fittings use brass bodies designed for copper, aluminum, and thermoplastic pipe. For plastic tubing add the correct insert to maintain tube support and a proper seal.
The temperature range spans from -65°F to +250°F (-53°C to +121°C). This broad window covers cold basements and warmer mechanical rooms while staying inside rated pressure limits.
Materials and construction
Brass construction is paired with rubber sealing components to provide shear resistance and reliable sealing. Series stainless steel parts, including 304 series stainless, are available for corrosion-prone installations.
Operating parameters
The couplings are intended for low- to medium-pressure liquid lines. They are not recommended for steel tubing or gaseous media. Vibration resistance is fair; choose a long nut if you need extra resistance to movement.
Tolerances and Standards
Machining holds +/- .02″ tolerance and meets ASA, ASME, and SAE requirements. Light Pattern (“L”) options adjust thread length while still remaining interchangeable with full pattern parts.
- Not lead free; they’re intended for plumbing and light industrial work such as sewer repair and routine coupling swaps.
- Inspect tube temperature ratings so components stay within the fitting’s envelope.
- Avoid excessive movement to preserve ferrule grip and rubber seal life.
| Feature | Value | Additional Notes | Best Use |
|---|---|---|---|
| Material Options | Brass / 304 series stainless options | Rubber seal and securing cage available | Copper, aluminum, thermoplastic pipe |
| Temperature | -65°F to +250°F | Refer to tubing temp for max pressure | Cold water and warm mechanical rooms |
| Dimensional Tolerance | +/- .02″ | ASA / ASME / SAE conformance | Precise alignments, repeatable torque |
| Limits | No steel tubing / no gaseous media | Fair vibration resistance; long nut for more | Low/medium pressure liquid applications |
Installation Parts Supply keeps these spec-driven parts on hand so you can meet jobsite requirements confidently and with fewer surprises.
Applications, Pipe Compatibility, and Installation Notes
Confirming material compatibility before cutting a tube saves time and helps prevent leaks later.
You can use these couplings with copper, aluminum, and thermoplastic tubing. When you use plastic tube, add the correct insert to support the wall and preserve the seal.
Designed for low- to medium-pressure liquid lines, these parts fit fixture supplies, appliance hookups, and light sewer repair tasks. They are not rated for gaseous media or steel tubing, so you should avoid those applications to remain within safe limits.
Tips for Installation
- Cut the tubing square and deburr lightly so the ferrule can seat evenly.
- Align the tube axis with the fitting body and hand-start the nut to avoid cross-threading.
- Tighten gradually to the recommended turn-of-nut and recheck after pressurizing.
- For higher vibration situations, choose a long nut and support nearby runs to reduce movement.
- Maintain clearance for future service so the nut, ferrule, and cage are accessible for inspection or repair.
| Material | Best Use | Notes |
|---|---|---|
| Copper / Aluminum | Fixture lines and appliance feeds | Straightforward installs; good seal with proper torque |
| Thermoplastic | Low-pressure water runs | Insert required to support tube wall |
| Steel | Not recommended | Avoid using; select couplings rated specifically for steel tubing instead |
Trust Installation Parts Supply to deliver the right inserts, long nuts, and accessory parts for a smooth install. Follow the checklist—confirm tube material, add an insert for plastic, align properly, tighten to spec, and recheck—to reduce callbacks and keep jobs on schedule.
Pricing, Availability, and Connected Solutions
Get clear pricing and quick availability so you can plan materials and labor with confidence.
Some manufacturers require retailers to follow a Minimum Advertised Price (MAP) rule. When an item is under MAP, the lowest price appears only after you add the product to your cart. You can view that price without commitment and remove the item any time.
Online Pricing: How It Works
MAP policies mean the checkout reveals the final low price for qualifying items. That approach protects manufacturer programs and still provides transparency for you. When price-checking, add the item to your cart to see the actual offer and remove it if you decide not to buy.
Related options and cost-saving combos
You can often save by choosing bundled parts or purpose-built valves instead of separate pieces.
- The John Guest Angle Stop Max Adapter Valve (SKU PPASV-6) sells each at $12.92 and is usually less expensive than buying a separate coupling and valve.
- Using bundles cuts part count, speeds under-sink installations, and lowers return risk because compatible components like cage inserts and clamping pieces are pre-matched.
- Fast fulfillment and clear inventory information help you line up pipe, steel parts, and sewer repair items so jobs remain on schedule.
| Purchase Option | Primary Use | Notes/Details |
|---|---|---|
| Single Coupling | Custom assemblies | Flexible option but may require additional parts |
| Angle Stop Valve (PPASV-6) | Fixture shutoff | $12.92; often lower total cost than separate valve and coupling |
| Bundle (valve + insert) | Under-sink installs | Speeds work and can reduce callbacks |
Shop Installation Parts Supply for competitive pricing, quick turnaround, and bundled solutions that simplify your cart.
Conclusion
When every joint matters, choosing the right part and support speeds installations and reduces callbacks.
By selecting the correct product and following installation guidance, you’re choosing a practical, code-conscious option for liquid supply lines. Match copper, aluminum, or thermoplastic tubing (use an insert for plastic) to get a reliable seal that’s easy to service later.
Steer clear of steel tubing and any gaseous media so installations stay safe and inside specification. Combine recommended valves with the correct cage and accessories to increase vibration resistance and long-term performance on sewer and fixture jobs.
Installation Parts Supply is ready to help you pick the right Max Adapter Compression Fittings and ship them fast anywhere in the United States. If you need help, support is available from selection through checkout so you can finish cleanly, on time, and within budget.
Common Questions
Which types of pipes are compatible with these compression connectors?
These compression connectors work with copper, aluminum, and many thermoplastic pipes, provided you use a proper insert for softer plastics. They are not recommended for standard steel tubing or for pressurized gaseous media. For cast iron, ductile iron, asbestos cement, and PVC sewers, check the product’s nominal diameter and sealing gasket compatibility before installing.
What are these connectors made of?
The bodies are brass with stainless steel components in key areas, plus a pliable rubber sealing gasket to ensure leak resistance. Some variants include 304 series stainless steel parts and a high-impact securing cage or clamping system for added strength and durability.
How well do these connectors handle vibration and shear forces?
They’re designed to withstand vibration and moderate shear forces thanks to the steel click-lock clamping and a cast iron or ductile iron rated cage in heavy-duty models. The rubber sealing gasket maintains a tight seal while the clamping system absorbs movement to protect joints from loosening.
Are these fittings suitable for cold-weather installation?
Yes. The rubber gasket stays pliable for easier installation in cold conditions, and stainless steel components resist embrittlement. For best results, follow torque guidelines and allow extra time for alignment when temperatures are very low.
What are the pressure and temperature limits for these connectors?
Typical operating parameters include low-to-medium pressure plumbing and temperature ranges of about -65°F to +250°F for compatible materials. Always confirm the specific model’s rating, especially when working near upper temperature or pressure limits.
Do these connectors meet industry standards?
A number of these connectors meet ASA/ASME/SAE tolerances with tight dimensional control, often around +/- .02. Check model certifications and material listings to ensure compliance with your project’s codes.
Are pipe inserts necessary when using plastic pipe?
Yes. For most thermoplastic pipes, an insert is recommended to prevent deformation and maintain proper sealing. The insert helps keep alignment and reduces the risk of leaks or failures under pressure.
How can I ensure proper pipe alignment during installation?
Make sure pipe ends are clean and square, use a guide or insert on plastics, and apply click-lock clamping evenly. With the securing cage and high-impact clamping system, alignment is maintained as you tighten to the recommended torque values.
Can these connectors be used for sewer repair and gravity flow systems?
Yes, certain models are suitable for sewer repair and gravity flow drainage when sized correctly for the nominal diameter and when the rubber sealing gasket is compatible with wastewater. Verify compatibility with iron, cast iron, and asbestos cement pipe types if they are part of the run.
How do pricing and availability work when ordering online?
Because pricing often follows MAP policy, the lowest available price usually appears in your cart at checkout. Installation Parts Supply and similar vendors list related options such as angle stop valves and cost-saving combos; compare these to find the best solution for your budget and job.
What related choices might help reduce overall cost?
Look for bundled valve-and-coupling combos, angle stop adapters, and multi-pack deals. Choosing stainless steel click-lock models only in areas where they’re necessary can save money while still putting steel components where strength matters most.
What is the expected life of the rubber sealing gasket in sewer or drainage service?
The service life will depend on exposure to chemicals, abrasion, and temperature. In typical sewer and gravity-flow applications, a high-quality rubber gasket paired with stainless steel components can last many years. Inspect the gasket periodically and replace it if you notice hardening or cracking.







