Sioux Chief 644X Series FSWT x...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$0.85
Sioux Chief 644X Series FSWT x PEX Barb Transition Adapter, Copper-to-PEX Fitting

Sioux Chief 644X Series FSWT x PEX Barb Transition Adapter, Copper-to-PEX Fitting

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Model: 644X2

In Stock (leaves warehouse same day if ordered before 3pm ET)

$0.85
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Sioux Chief 644X Series FSWT x PEX Barb Transition Adapter, Copper-to-PEX Fitting

The Sioux Chief 644X Series FSWT x PEX Barb Adapter delivers a code-ready transition between female sweat (FSWT) copper fittings and PEX barb tubing for rough-in, remodel, and repair work behind the wall. This Copper-to-PEX Transition Fitting is available across the 644X Series in 1/2", 3/4", and 1" FSWT x PEX Barb configurations (models 644X2, 644X3, and 644X4), letting plumbers convert a copper supply run to PEX without replacing the entire line. Manufactured in the United States and packaged 1000 EA per carton, the series is built for high-volume contractor and distributor stocking programs.

Key Features

  • Trade Size Range: Available in 1/2", 3/4", and 1" FSWT x PEX Barb configurations to match the copper-to-PEX transition needed on the job.
  • Connection Type: Female sweat (FSWT) solder joint on one end and a PEX barb fitting on the other, secured with a standard clamp or crimp ring for a leak-resistant joint.
  • Series Platform: Part of the Sioux Chief 644X Series, spanning models 644X2, 644X3, and 644X4 built on the same FSWT x PEX Barb design.
  • Country of Origin: Manufactured in the United States for consistent dimensional accuracy from batch to batch.
  • Bulk Packaging: Supplied 1000 EA per carton, suited to high-volume contractor use, wholesale distribution, and inventory-efficient warehouse stocking.
  • Application-Ready Design: Bridges copper and PEX systems using standard sweat-soldering and PEX-crimping tools already on a plumbing truck.

Technical Specifications

  • Trade Size Range: 1/2" - 1"
  • Connection Type: FSWT x PEX Barb
  • Series: 644X Series (644X2, 644X3, 644X4)
  • Country of Origin: United States
  • Packaging: 1000 EA per carton

Typical Applications

  • Residential and Commercial Plumbing Installations
  • Copper-to-PEX Transition Connections
  • Water Supply Line Repairs and Retrofits
  • New Construction Plumbing Rough-In
  • Remodel and Renovation Piping Upgrades

Why Sioux Chief?

Sioux Chief builds the 644X Series FSWT x PEX Barb Adapter for dependable copper-to-PEX transitions, backed by United States manufacturing and bulk 1000 EA carton packaging suited to professional plumbing workflows. Contractors, remodelers, and distributors rely on Sioux Chief fittings across models 644X2, 644X3, and 644X4 for consistent fit and steady availability in residential and commercial rough-in projects, spanning the full 1/2" to 1" size range for stocking programs.

Product Specs

Country Of Origin:
United States
Product Type:
Adapter
Connection Type:
FSWT x PEX Barb
Series:
644X Series
Department:
Plumbing
Product Group:
Rough-In and Supports
Product Subgroup:
Fittings and Valves
Product Size:
1/2" - 1"
Country of Origin:
USA

Sioux Chief 644X2 – Frequently Asked Questions

1) How does the Sioux Chief 644X adapter connect copper pipe to PEX?
One end is a female sweat (FSWT) socket that you solder onto copper tubing, and the other end is a PEX barb that you push into the PEX and secure with a clamp or crimp ring. So the joint is made with the same torch and crimp or cinch tool already on the truck, no proprietary tooling.
2) What sizes does the 644X Series copper-to-PEX adapter come in?
Three trade sizes across the series: 1/2 inch (644X2), 3/4 inch (644X3), and 1 inch (644X4). Both ends match the trade size, so a 3/4 inch body sweats to 3/4 inch copper and barbs into 3/4 inch PEX.
3) Can I use this to convert part of an existing copper line to PEX without redoing the whole run?
That is exactly the use. You cut into the copper, sweat the FSWT end onto the existing line, and continue in PEX from the barb. Common on repairs, remodel piping upgrades, and partial repipes where the rest of the copper supply stays in place.
4) Does the female sweat end accept copper tube or a male copper fitting?
It is a female socket, so it slips over the outside of the tube or over a male-end fitting of the same nominal size and is soldered. If you need to connect into a female copper socket instead, you want a male sweat x PEX adapter rather than the 644X.
5) Do I solder the fitting before or after inserting the PEX?
Solder first, with the PEX out of the fitting. Heating the body with tubing already barbed in will damage the PEX. Let the fitting cool, then insert the tubing and set the clamp or crimp ring.
6) How is the 644X adapter packaged, and is there a smaller count for a single job?
The 644X Series ships 1000 each per carton, which is bulk packaging aimed at contractor stocking programs and wholesale distribution rather than a one-off repair.
7) Are Sioux Chief 644X adapters made in the USA?
Yes, the 644X Series is manufactured in the United States, which matters on jobs with domestic-sourcing requirements for government, institutional, or federally funded work.
8) Will a clamp (cinch) ring work on this barb, or do I need a copper crimp ring?
Either. The barb is designed to be secured with a standard clamp or crimp ring, so stainless cinch clamps or copper crimp rings both work as long as the ring matches the PEX size you are using.
9) Is this adapter suitable for commercial water supply rough-in, not just residential?
It is used in both. Typical applications span new construction rough-in, residential and commercial potable water supply installs, repairs, and remodel piping upgrades behind the wall.
How fast can I get the Sioux Chief 644X2 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Sioux Chief 644X2 come with a warranty?
Absolutely. The Sioux Chief 644X2 is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Sioux Chief 644X2?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Sioux Chief 644X2 from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
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