Midland Industries 700066-0406 Female Coupling Brass

Product Description

The MIDLAND INDUSTRIES 700066-0406 is a lead-free brass female coupling designed to connect 1/4-inch compression tubing to a 3/8-inch female NPTF threaded port. The compression end accepts copper, aluminum, or plastic tubing, while the NPTF female thread provides a dry-seal mechanical connection without relying solely on sealant. Rated for temperatures from -40 degrees F to 250 degrees F, this fitting suits a wide range of fluid and gas plumbing applications. The lead-free brass construction meets regulatory requirements for potable water and domestic plumbing systems. It is a compact, single-piece fitting intended for licensed plumbers and qualified trades working on water supply, refrigeration, or gas distribution lines.

This coupling is suited for residential and light commercial plumbing installations where a compression tube line must transition to a female NPTF threaded connection on a valve, manifold, or equipment port. Compatible with copper, aluminum, or plastic tubing on the compression side, it fits common service scenarios such as water supply connections, ice maker lines, and similar low-to-medium-pressure plumbing runs. The 7/16-24 compression thread and 3/8-18 NPTF thread sizing are standard in these applications, making this fitting a direct-fit option for typical transition points in the system.

Key Features

• Lead-free brass construction meets potable water compliance requirements
• 1/4-inch compression inlet accepts copper, aluminum, or plastic tubing
• 3/8-inch female NPTF outlet provides a dry-seal threaded connection
• Rated from -40 degrees F to 250 degrees F for broad service range
• Compact profile at approximately 1.1 inches in length and 0.75 inches in height
• Thread sizes: 7/16-24 compression x 3/8-18 NPTF

Compatibility

Designed for use with copper, aluminum, or plastic tubing on the compression side. Suitable as an OEM-style replacement or new-install fitting wherever a 1/4-inch compression to 3/8-inch female NPTF transition is required in plumbing or fluid-handling systems.

Installation Notes

Installation should be performed by a licensed plumber in accordance with applicable IPC or local plumbing codes. Shut off the water supply and relieve system pressure before disassembling or installing any compression fitting. Hand-tighten the compression nut first, then advance with a wrench - do not overtighten, as this can crack the ferrule or deform the tubing. NPTF threads are designed for dry-seal engagement, but applying thread sealant tape per job-site requirements is acceptable practice.