Parker 37PTCSP-6-4 Push-to-connect Stem Adapter 3/8 X 1/4 in

Product Description

The PARKER 37PTCSP-6-4 is a push-to-connect stem adapter tube fitting designed to join tubing with two different outside diameters in a single inline connection. It accepts 3/8-inch OD tubing on one end and 1/4-inch OD tubing on the other, making it a direct solution for reducing or transitioning between tube sizes without additional fittings. Constructed from brass with Buna-N seals and a nylon body component, this fitting is rated to 250 psi maximum working pressure. It is installed by plumbers, HVAC technicians, and fluid-handling specialists working with push-to-connect pneumatic or fluid control systems.

This stem adapter fitting is suited for residential and light commercial applications where push-to-connect tube lines require a transition between 3/8-inch and 1/4-inch OD tubing. Typical install scenarios include HVAC equipment fluid lines, pneumatic control circuits, and plumbing supply connections where a quick, tool-free tube transition is needed. The push-to-connect design allows fast insertion and secure locking without ferrules, threads, or compression sleeves at the tube end.

Key Features

• Transitions between 3/8-inch and 1/4-inch OD tubing in a single push-to-connect fitting
• Rated to 250 psi maximum working pressure
• Brass construction with Buna-N seals for fluid compatibility and durability
• Nylon component supports lightweight, corrosion-resistant installation
• Tool-free tube insertion for fast field assembly
• Compact envelope: 1.66 inches height, 1.66 inches length, 0.75 inches width

Compatibility

Designed as an OEM-style push-to-connect stem adapter replacement for pneumatic and fluid control tubing systems using 3/8-inch and 1/4-inch OD tubing lines.

Installation Notes

This fitting is installed by licensed plumbers or HVAC technicians. Before installation, shut off and depressurize the fluid or pneumatic line completely. Ensure tubing ends are cut cleanly and squarely, free of burrs, to achieve a proper seal at the push-to-connect collet. Do not exceed the 250 psi rated working pressure, and verify that the tubing material and fluid media are compatible with brass and Buna-N prior to installation.