B K Mueller 521-708HN 2 Inch Black Union Brass Iron

Product Description

The B K Mueller Industries 521-708HN is a 2-inch black union fitting constructed from brass and iron, designed for use in gas piping systems and related black iron pipe installations. Unions allow a threaded pipe run to be disconnected and reconnected without rotating the pipe itself, making them essential for serviceable appliance connections. This fitting is sold in a package of 3 units and weighs 6.32 pounds per package. It is a standard trade-supply component installed by licensed plumbers, gas fitters, and HVAC technicians on both residential and light commercial projects.

This union is suited for black iron pipe systems commonly found in natural gas and propane distribution lines within residential and commercial buildings. Typical applications include connecting gas appliances such as furnaces, boilers, water heaters, and commercial cooking equipment where future serviceability and disconnect capability are required. The brass seat construction provides a reliable, leak-resistant union joint appropriate for gas service environments.

Key Features

• 2-inch nominal pipe size for use in standard black iron pipe systems
• Brass and iron construction for durability in gas service applications
• Union design allows pipe disconnection without rotating the pipe run
• Sold in a package of 3 units for multi-connection jobs
• Threaded connection type consistent with standard black iron pipe fittings

Compatibility

Designed as an OEM-style replacement and standard fitting for 2-inch black iron threaded pipe systems used in gas distribution and related piping applications.

Installation Notes

Installation of gas pipe fittings must be performed by a licensed plumber or gas fitter in accordance with local codes and the International Fuel Gas Code (IFGC). Shut off the gas supply and verify zero pressure at the work area before disassembling or installing any union fitting. Apply an approved pipe thread sealant or PTFE tape rated for gas service to all threaded connections. Pressure-test the completed assembly per local code requirements before returning the system to service.