PEX Pipe Fittings Names: The Complete Visual Catalog for Wholesale Buyers

Published by IFANPRO · Updated June 2025 · 12 min read

If you import or wholesale plumbing supplies, you already know that PEX has replaced copper in the majority of residential and light-commercial projects across North America, Europe, and the Middle East. What separates a profitable plumbing aisle from a returns-heavy one is simple: stocking the right fitting names, sizes, and connection types.

This reference page lists every PEX pipe fitting by name, function, available size, material option, and governing standard. Use it as a checklist when building your next purchase order or when training new sales staff on the PEX category.

1. PEX Couplings

A coupling connects two lengths of PEX pipe in a straight line. It is the most frequently ordered fitting in any PEX system and the first item on every wholesaler’s replenishment list.

Straight couplings join two pipes of the same diameter. A typical straight coupling for 1/2" PEX measures approximately 2" to 2-1/2" overall length (varies by manufacturer) with a barbed or crimp stem on each end. Part number format from most manufacturers follows a pattern like PEX-C-1/2 (coupling, 1/2 inch).

Reducing couplings transition between two different pipe diameters — for example, 3/4" to 1/2". These are common in manifold trunk lines where branch sizes step down. Reducing couplings carry a higher unit price and lower return rate, making them a margin-positive SKU for wholesalers.

2. PEX Elbows

Elbows change the direction of a PEX run. They come in two standard angles and multiple connection variants.

90° elbows make a right-angle turn. These are used at inside corners, around structural obstructions, and wherever a pipe run must drop vertically. A 90° elbow for 1/2" PEX typically has a center-to-end measurement of approximately 1" to 1-1/2" (varies by manufacturer).

45° elbows provide a gentler directional change. Specifiers prefer them in radiant floor heating loops where sharp bends increase pressure drop.

Male threaded elbows (MPT) combine a 90° bend with a male threaded port, usually NPT, allowing connection to a threaded fixture supply or a metal pipe stub-out. Common sizes: 1/2" crimp × 1/2" MIP.

Female threaded elbows (FPT) mirror the male version but accept a male threaded pipe. Used where a wall-mounted fixture needs a supply connection at an angle.

3. PEX Tees

Tees split a single supply line into two branches, forming a “T” shape. They are the second-highest volume SKU after couplings.

Equal tees have all three outlets at the same diameter. A 1/2" equal tee is the single most common tee in residential plumbing.

Reducing tees step one or more branches down in size. Example: 3/4" run × 1/2" branch. These eliminate the need for a separate coupling plus reducer combination.

Male threaded tees feature one or more NPT threaded ports. Typical use: connecting a PEX branch to a threaded valve or appliance supply.

Female threaded tees accept threaded pipe on one or more ports. Often specified when transitioning from a threaded manifold to PEX distribution.

4. PEX Adapters

Adapters connect PEX to a different material or connection method. They are critical for remodel work and for any job where PEX meets copper, CPVC, or threaded steel.

Male adapters have a PEX connection on one end and male NPT threads on the other. Used to screw into a female-threaded valve, union, or equipment connection.

Female adapters accept male threaded pipe on one end and connect to PEX on the other.

Transition adapters join PEX directly to copper or CPVC without threading. Solder-end transition adapters (PEX × sweat copper) are popular with contractors who want to keep existing copper stub-outs. Slip-fit transition adapters use a stainless-steel grab ring and O-ring seal for a no-solder connection to copper.

For wholesale buyers, transition adapters carry a higher margin than standard couplings. Stocking both 1/2" and 3/4" sweat-transition and threaded-transition variants covers most common field requirements.

5. PEX Unions

A union is a three-piece fitting — a nut, a female end, and a male end — that allows a section of pipe to be disconnected without cutting. Unions are specified at equipment connections (water heaters, boilers, chillers) and at any point where future maintenance access is expected.

PEX unions are available in crimp, clamp, and push-fit versions. Brass-body unions with EPDM O-rings are rated for working pressures up to 200 psi at 180°F (ASTM F877). For wholesale stocking, 1/2" and 3/4" unions in DZR brass are the priority SKUs.

6. PEX Cross Fittings

Cross fittings have four outlets arranged in a plus-sign (+) pattern. They distribute flow in four directions from a single junction point.

In residential plumbing, crosses appear at manifold distribution points and in multi-fixture wet walls. In radiant heating, they show up in manifold header assemblies.

Cross fittings are lower-volume than tees but essential for complete system design. Standard sizes: 1/2" and 3/4" equal cross. Reducing crosses (e.g., 3/4" × 1/2") are available from most major manufacturers on indent order.

7. PEX Caps and Plugs

Caps seal the open end of a PEX pipe permanently. Used to close unused branch lines, terminate test lines, or finish a run that may be extended later. Caps are cemented, crimped, or clamp-connected depending on the system type.

Plugs insert into the open end of a fitting or valve port. They are typically threaded (male NPT) and used during pressure testing or to temporarily seal a port before final fixture installation.

Caps and plugs are low-cost, high-margin items. A bag of 25 pcs in 1/2" size is a typical wholesale pack configuration offered by many suppliers. Keep both crimp-end caps and threaded plugs in stock.

8. Manifold Connections

Manifold connections are the fittings that join PEX tubing to a distribution manifold. They include:

• Manifold adapters — FPT or MPT fittings that screw into manifold port openings (typically 3/4" or 1" manifold port × 1/2" or 3/4" PEX crimp).
• Manifold mount brackets — not fittings per se, but often ordered alongside connection fittings.
• Shut-off valve adapters — integrated ball-valve units at each manifold port, combining a shut-off and a PEX connection in one piece.

Manifold hardware is a growing category as home-run (manifold) PEX systems gain share over traditional trunk-and-branch layouts. Wholesalers who bundle manifold adapters with their manifold sales see higher attach rates.

9. Connection Types: Crimp vs. Clamp vs. Push-Fit

The fitting body is only half the equation. The connection method determines installation speed, tool cost, and code acceptance.

Crimp remains the dominant method in new construction. The copper ring is swaged over the pipe and fitting barb using a crimp tool. A go/no-go gauge verifies the crimp diameter. Crimp fittings are rated under ASTM F877 for the fitting body and ASTM F1807 for the copper crimp ring.

Clamp (also called cinch) uses a stainless steel ring positioned over the pipe, then compressed with a cinch tool until the ring ear shears at the correct tension. The advantage: many cinch tool models accept a single head that fits sizes from 3/8" to 1-1/4", reducing tool inventory for field crews.

Push-fit fittings require no tools. The pipe is cut, deburred, and pushed into the fitting until it seats. An internal stainless grab ring prevents pull-out; an EPDM O-ring provides the seal. Push-fit is governed by ASTM F2159 and is gaining ground in markets where labor cost is the primary constraint.

10. PEX-A vs. PEX-B vs. PEX-C: Fitting Compatibility

All three PEX types — PEX-A (Engel method), PEX-B (silane method), and PEX-C (electron beam / radiation method) — use the same fitting bodies. A 1/2" brass crimp elbow works identically on PEX-A, PEX-B, and PEX-C tubing of the same nominal size.

The difference lies in the tubing’s memory and flexibility:

For wholesale buyers, PEX-B accounts for the largest global volume and pairs with crimp and clamp fittings. PEX-A dominates the North American market where expansion fittings (Uponor Wirsbo system) are specified. PEX-C is common in European imports and works with all three connection methods but benefits from push-fit due to its stiffness.

The key point for your catalog: fitting bodies are cross-compatible. Your crimp elbows, tees, and couplings sell to PEX-A, PEX-B, and PEX-C customers alike. Only the connection ring or expansion tool differs.

11. Sizing Guide: Imperial and Metric

PEX fittings are sized by the outside diameter (OD) of the tubing they connect. The two sizing systems are:

Wholesale stocking priority: 1/2" and 3/4" account for approximately 70% of residential PEX fitting orders. Stock 3/8" and 1" at moderate depth. Carry 1-1/4" as a special-order item unless you serve commercial accounts.

12. Complete Fitting Reference Table

The table below consolidates every PEX fitting type with its available sizes, connection options, material choices, and governing standards. Use this as a single-page reference for purchase orders.

13. Standards and Certifications to Verify

When sourcing PEX fittings for import or wholesale, confirm that the manufacturer holds documentation for these standards:

• ASTM F877 — Standard specification for plastic (PEX) hot- and cold-water distribution fittings (covers the fitting body dimensions, pressure ratings, and material requirements).
• ASTM F1807 — Standard specification for copper crimp rings used with PEX fittings.
• ASTM F2098 — Standard specification for stainless steel clamp rings.
• ASTM F2159 — Standard specification for plastic push-fit fittings for PEX pipe.
• CSA B137.5 — Canadian standard for PEX tubing and fittings; required for any product sold into the Canadian market.
• NSF/IAPMO 61 & 372 — Potable water safety (NSF 61) and lead-free compliance (NSF 372, ≤0.25% lead on wetted surfaces). Mandatory for any fitting used in drinking water systems in the US and Canada.
• UPC / cUPC listing — IAPMO’s Uniform Plumbing Code listing; required by most North American building inspectors.

IFANPRO’s PEX fittings are manufactured under ISO 9001 quality management, tested per ASTM F877, and carry CE, WRAS, and NSF/IAPMO certifications. Every fitting is produced from lead-free DZR (dezincification-resistant) brass alloy CW617N or high-performance PPSU polymer, meeting both NSF 61 and NSF 372 requirements.

14. Stocking Recommendations for Wholesalers

Based on order data from import and wholesale buyers across North America and Europe, here is a recommended initial stocking mix:

Start with crimp fittings (they cover the widest customer base) and add clamp and push-fit lines as demand develops. Always stock reducing fittings and threaded variants at 30–50% of the depth of equal-size fittings.

Watch: Step-by-step PEX crimp fitting installation — the most common connection method in new construction.

Frequently Asked Questions

Can I use the same PEX fittings for PEX-A, PEX-B, and PEX-C pipe?

Yes. The fitting body (elbow, tee, coupling, etc.) is the same for all three PEX types when using crimp or clamp connection methods. The difference is in the tubing itself, not the fitting. A 1/2" brass crimp elbow works on PEX-A, PEX-B, and PEX-C tubing of the same nominal size. The only exception is the expansion fitting system (Uponor/Wirsbo), which uses a larger ID fitting designed specifically for PEX-A expansion connections.

What is the most common PEX fitting size for residential plumbing?

1/2" (20 mm) is the single most common size, used for branch lines to individual fixtures (sinks, toilets, showers). 3/4" (25 mm) is the standard trunk line and manifold feed size. Together, these two sizes account for roughly 70% of all residential PEX fitting purchases. 3/8" is used for appliance supply lines, and 1" is used for service entrance lines.

What is the difference between ASTM F877 and ASTM F1807?

ASTM F877 covers the fitting body itself — dimensions, pressure ratings, material requirements, and performance tests for the plastic or brass fitting. ASTM F1807 covers the copper crimp ring used to secure the fitting to the PEX pipe. When ordering, you need fittings that meet F877 and crimp rings that meet F1807. The two standards work together as a system.

Which connection method should I stock for my wholesale market?

Crimp (ASTM F1807) is the safest choice for initial stocking. It has the broadest code acceptance, the largest installer base, and the most competitive pricing. Clamp (cinch) is growing fast because the single-size tool reduces field crew costs. Push-fit (ASTM F2159) is the fastest-growing segment, driven by labor savings, but carries a higher per-unit fitting cost. If you can only stock one type, start with crimp. If your market is labor-cost-sensitive, add push-fit as a premium tier.

Request Wholesale Pricing

IFANPRO manufactures a complete range of PEX pipe fittings in DZR brass and PPSU, covering every fitting type listed above in sizes from 3/8" to 1-1/4". Our 120,000 m² production facility holds ISO 9001, ISO 14001, CE, WRAS, and NSF/IAPMO certifications, and we supply import and wholesale buyers across 60+ countries.

Download our PEX fittings catalog for full part numbers, dimensional drawings, and pricing tiers. Or contact our export team directly:

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