Parker A6UC5-MG Push-to-connect Union Fitting

Product Description

The PARKER A6UC5-MG is a push-to-connect union tube fitting designed to join two tubes of differing outside diameters — 3/8 inch and 5/16 inch OD — in a single inline connection. Constructed from polyoxymethylene (POM), a rigid engineering-grade acetal resin, this fitting delivers a rated working pressure of 300 psi. Installation requires no tools: tubing inserts directly into the fitting body and locks in place via an internal collet. The low-profile union design keeps plumbing runs compact in tight spaces. Weighing approximately 0.02 pounds, it adds minimal mass to the assembly. HVAC technicians, plumbers, and fluid-system installers use this style of fitting for instrument tubing, pneumatic lines, and low-pressure fluid circuits.

The A6UC5-MG is suited for applications involving small-diameter tubing in residential and light commercial environments. Typical uses include pneumatic control lines, HVAC condensate and sensing tubing runs, refrigeration instrument lines, and other low-pressure fluid or air circuits where a quick, reliable tube-to-tube union connection is needed. The reducer union configuration — 3/8 inch OD on one side and 5/16 inch OD on the other — makes it practical for transition points where tubing size changes within the same run.

Key Features

• Push-to-connect collet design — tool-free tube insertion and secure lock
• Reducer union configuration joins 3/8 inch OD and 5/16 inch OD tubing in one fitting
• Polyoxymethylene (POM) body — rigid, chemically resistant acetal construction
• 300 psi working pressure rating
• Tan color body for quick visual identification in multi-line installations
• Lightweight at 0.02 pounds — minimal load on tubing runs

Compatibility

Designed as an OEM-style push-to-connect union replacement for small-diameter tubing systems using 3/8 inch and 5/16 inch OD tube sizes in pneumatic and low-pressure fluid circuit applications.

Installation Notes

Installation is performed by licensed HVAC technicians or plumbers working on instrument and control tubing lines. Before installing or removing this fitting, depressurize and isolate the tubing circuit completely. Ensure tubing ends are cut cleanly and squarely with a proper tube cutter — ragged or angled cuts will compromise the collet seal. To release the fitting, depress the collet release ring evenly while withdrawing the tube; do not force or twist the tube body against the fitting housing.