Sioux Chief 654X2GPK2 1/2" F1807 PEX x 1/2" PB Transition Coupling

Sioux Chief 654X2GPK2 1/2" F1807 PEX x 1/2" PB Transition Coupling

The Sioux Chief 654X2GPK2 is a 1/2" F1807 PEX x 1/2" PB transition coupling built for rough-in plumbers connecting new PEX crimp tubing to existing polybutylene (PB) pipe runs. One end accepts a 1/2" F1807 PEX crimp connection while the opposite end mates to 1/2" polybutylene pipe, letting a crew extend, repair, or partially re-route a PB system without cutting back to a full repipe. It is a straightforward, behind-the-wall fitting sized for standard 1/2" rough-in runs, meant to be installed under a floor, inside a wall cavity, or in a crawlspace rather than displayed as a finished fixture. Because it bridges two different pipe materials at one fixed trade size, it is intended for point-of-repair transitions rather than as a general-purpose coupling for matched pipe systems.

Key Features

• Trade Size: 1/2" x 1/2", matching common 1/2" PEX tubing and 1/2" polybutylene branch and supply runs found in residential rough-in.
• F1807 Crimp End: One end is sized to ASTM F1807 PEX crimp dimensions, accepting a standard copper crimp ring and crimp tool for a secure, mechanically set PEX termination.
• PB Transition End: The opposite end connects directly to existing 1/2" polybutylene pipe, allowing a plumber to tie new PEX tubing into a legacy PB system at the exact point of repair.
• Repair-Friendly Design: Purpose-built for retrofit and repair work where only a section of an aging polybutylene run needs to be replaced, rather than the entire branch or riser.
• Single-Piece Coupling: A one-piece body carries both connection ends, keeping the transition to a single fitting rather than stacking multiple adapters at the repair point.
• Compact Rough-In Fitting: Sized and configured for behind-the-wall and under-floor installation alongside other rough-in plumbing components in the same run.

Technical Specifications

• Refer to manufacturer documentation for complete technical specifications.

Typical Applications

• Polybutylene (PB) Pipe Repair and Retrofit
• PEX-to-Polybutylene System Transitions
• Residential Rough-In Plumbing Repairs
• Behind-the-Wall and Under-Floor Supply Line Connections
• Point-of-Failure Repairs on Older Polybutylene Runs
• Renovation Work on Homes Still Plumbed with Polybutylene Pipe

Why Sioux Chief?

Sioux Chief is a trade-focused manufacturer of rough-in plumbing fittings, and the 654X2GPK2 reflects that focus with a simple, single-purpose transition coupling sized to match standard 1/2" F1807 PEX crimp and 1/2" polybutylene connections. For plumbers and contractors working on legacy PB systems, it offers a direct way to bring a repair up to current PEX tubing without reworking the entire run, keeping labor and material focused on the section that actually needs replacing. Stocking this transition coupling lets a service plumber respond to a polybutylene failure with a PEX-compatible repair on the same truck run.