Midland Industries 12213 Master Cylinder Adapter Brass

Product Description

The MIDLAND INDUSTRIES 12213 is a dual master cylinder adapter designed to connect brake lines at the master cylinder port in automotive and light-duty hydraulic brake systems. Machined from brass, this fitting transitions a 3/16-inch female inverted flare connection to a 5/16-inch male inverted flare connection, with thread specifications of 3/8-24 on the female end and 1/2-20 on the male end. It is rated to 1900 psi and handles temperatures from -65 to 250 degrees F. The sealing surface is located on the hex face, providing a reliable metal-to-metal seal when properly torqued. Licensed plumbers, brake system technicians, and fleet maintenance professionals are the primary installers of this fitting.

This adapter is used when replacing or servicing dual master cylinders on passenger vehicles, light trucks, or other equipment that uses inverted flare brake line fittings. It bridges the size difference between two inverted flare brake line ports, eliminating the need for custom-fabricated adapters or non-standard line routing. Typical installation occurs during master cylinder replacement, brake system rebuilds, or hydraulic line repairs where a direct port-size mismatch exists between the cylinder and the existing brake line.

Key Features

• Dual-port adapter transitions 3/16-inch female inverted flare to 5/16-inch male inverted flare
• Thread sizes: 3/8-24 female x 1/2-20 male, matching standard SAE inverted flare specifications
• 1900 psi maximum working pressure suitable for hydraulic brake system demands
• Operating temperature range of -65 to 250 degrees F for broad service conditions
• Seals on hex face for consistent, leak-resistant metal-to-metal contact
• Brass construction resists corrosion and is compatible with standard brake fluid formulations

Compatibility

Designed as an OEM-style replacement fitting for hydraulic brake systems using standard SAE inverted flare brake line connections at dual master cylinder ports.

Installation Notes

Installation should be performed by a qualified brake system technician or licensed plumber familiar with hydraulic brake line fittings. Depressurize the brake system and isolate the master cylinder before removing any existing fittings. Use a proper flare nut wrench to avoid rounding the hex; do not use open-end wrenches alone on brake fittings. After installation, bleed the brake system completely and inspect for leaks before returning the vehicle or equipment to service.