A 90° elbow that connects a 3/8″ male pipe thread (MNPT) port to 1/4″ OD quick-connect tubing — the cross-size adapter for systems that mix 3/8″ threaded components with 1/4″ tubing lines. Sold as a 2-pack.

What it does

This elbow connects a 3/8″ MNPT threaded port to 1/4″ OD tubing at a 90-degree angle. The threaded side screws into the port with PTFE tape; the push-fit side accepts 1/4″ OD tubing tool-free.

Common use: under-sink cold-water supply valves (which typically have 3/8″ ports) feeding a 1/4″ RO system line. Also used on any component with a 3/8″ MNPT port where you want to run 1/4″ tubing.

Key benefits

• ✓3/8″ MNPT × 1/4″ OD QC — cross-size thread-to-tube adapter
• ✓90° elbow — space-saving turns in tight installs
• ✓Push-to-connect tube side — tool-free 1/4″ tubing connection
• ✓Bridges 3/8″ threaded ports to 1/4″ tubing lines
• ✓Common for cold-water supply valve to RO system connections
• ✓2-pack with automatic quantity discounts

Specifications

Compatibility

Often used with

Good to know before you buy

• Wrap the 3/8″ MNPT threads with PTFE tape (2–3 turns clockwise) before threading in.
• Hand-tighten, then snug slightly. Do not over-torque.
• Push 1/4″ OD tubing firmly into the quick-connect port until it seats.
• Check all connections for leaks before putting the system into service.