B K/mueller Inds 521-354HN Black Reducing Coupling 10 Pack

Product Description

The B K/MUELLER INDS(IMPORT) 521-354HN is a black reducing coupling designed to connect a 1-inch pipe to a 3/4-inch pipe in threaded piping systems. This fitting reduces pipe diameter at a junction point, making it a standard component in gas distribution, compressed air, and industrial fluid systems. The black finish indicates a malleable iron or black steel construction, appropriate for natural gas and propane service. Plumbers and pipefitters install this coupling when transitioning between pipe sizes within a run. Each order contains 10 couplings, sold as a unit, making this suitable for service trucks, supply stocking, or multi-point installations.

This reducing coupling is used in residential and commercial piping applications where a 1-inch line must transition down to a 3/4-inch branch or appliance connection. Typical install scenarios include gas supply lines, black iron distribution manifolds, boiler piping, and industrial compressed air runs. The threaded ends accept standard NPT pipe threads, allowing quick assembly with pipe wrenches and thread sealant.

Key Features

• Reduces from 1-inch to 3/4-inch pipe for in-line diameter transitions
• Black finish suitable for natural gas and propane piping service
• Threaded NPT connections for standard assembly with pipe wrenches
• Sold in a package of 10 for jobsite stocking and multi-point installs
• Compact reducing coupling profile fits tight piping arrangements

Compatibility

Designed as an OEM-style replacement or standard-stock reducing coupling for 1-inch to 3/4-inch NPT threaded black iron or steel pipe systems.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter in accordance with applicable codes, including IFGC requirements for gas piping. Shut off the gas supply or isolate the piping system and depressurize before beginning work. Apply an approved pipe thread sealant or PTFE tape rated for the service medium to all threaded joints before assembly. Pressure-test the completed assembly per local code requirements before returning the system to service.