Midland Industries 18188 Brass Compression Adapter

Product Description

The MIDLAND INDUSTRIES 18188 is a brass male adapter fitting that connects 3/8-inch compression tubing to a 1/4-inch Male NPTF threaded port. It is designed for use in plumbing, HVAC, and refrigeration applications where a secure, leak-resistant transition between compression and NPT threaded connections is required. The fitting handles working pressures up to 200 psi and an operating temperature range of -65 to 250 degrees F. The 9/16-24 x 1/4-18 thread specification and 0.56-inch hex allow for standard wrench installation. Licensed plumbers and HVAC technicians are the primary installers of this type of fitting.

The 18188 adapter is suited for residential and light commercial plumbing, HVAC refrigerant line accessories, and instrumentation tubing runs. It is compatible with copper, aluminum, and thermoplastic tubing on the compression side. The center-to-end dimension of 1.16 inches makes it well suited for tight-space installations where fitting length is a factor. It is a standard compression male adapter used wherever a compression tube line must terminate at an NPTF-threaded port on a valve, manifold, or equipment fitting.

Key Features

• 3/8-inch compression inlet transitions to 1/4-inch Male NPTF outlet
• Rated to 200 psi working pressure
• Operating temperature range: -65 to 250 degrees F
• 0.56-inch hex for standard wrench installation
• Compatible with copper, aluminum, and thermoplastic tubing
• Brass construction for corrosion resistance and reliable sealing

Compatibility

Designed for use with copper, aluminum, and thermoplastic tubing on the compression side. Suitable for any application requiring a 3/8-inch compression to 1/4-inch Male NPTF brass adapter in plumbing, HVAC, or instrumentation systems.

Installation Notes

Installation is performed by licensed plumbers or HVAC technicians. Shut off the water or gas supply and relieve system pressure before making or breaking any fitting connection. Use an appropriately sized open-end or adjustable wrench on the hex; do not over-tighten, as brass fittings can be damaged by excessive torque. Ensure the compression nut and ferrule are correctly seated on the tubing before tightening to avoid leaks.