B K/mueller Inds(import) 521-703HN Black Union 1/2 Inch

Product Description

The B K/MUELLER INDS(IMPORT) 521-703HN is a 1/2 inch black union fitting constructed from brass and iron. Unions allow a pipe run to be disconnected and reconnected without cutting or unthreading the entire line, making them a standard component in gas and water distribution systems where future serviceability matters. At 5.66 pounds per package of 15 units, this fitting is suited for rough-in and retrofit work on residential and light commercial piping systems. Licensed plumbers and pipefitters are the primary installers for this type of union in code-governed installations.

This 1/2 inch black union is appropriate for use in gas distribution piping, steam lines, and other applications where black iron or brass fittings are specified. The 1/2 inch size fits standard half-inch pipe schedules common in residential gas supply lines and low-pressure steam systems. It is sold in packages of 15 units, making it practical for contractors stocking materials for multiple jobs or service fleets.

Key Features

• 1/2 inch pipe size fits standard half-inch threaded pipe
• Brass and iron construction for durability in gas and steam service
• Black finish typical of gas-rated iron pipe fittings
• Union design allows pipe disconnection without disturbing upstream or downstream fittings
• Packaged in quantities of 15 units per package

Compatibility

Designed as an OEM-style replacement or new-installation fitting for standard 1/2 inch threaded black iron pipe systems.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable local codes and the International Fuel Gas Code or International Plumbing Code where gas or water service is involved. Shut off the gas or water supply and relieve system pressure completely before disassembling or installing any union fitting. Apply appropriate thread sealant rated for the service medium — use only gas-rated compound or tape on gas lines. Do not overtighten the union nut; hand-tighten and then use a pipe wrench to snug, checking for leaks after restoring system pressure.