B K Mueller 521-805HN 1 Inch Black Plain Plug 10 Pack

Product Description

The B K Mueller Industries 521-805HN is a 1-inch black plain plug designed to cap and seal pipe ends in plumbing and gas distribution systems. This plug is sold in a package of 10 units, making it practical for service vans and job-site stock. The black iron construction suits threaded pipe assemblies where a durable, corrosion-resistant end cap is needed. Licensed plumbers and pipefitters install this type of plug during pressure testing, system commissioning, or whenever a run needs to be terminated without a permanent weld or solder connection.

This plain plug is suited for residential and light commercial plumbing, gas piping, and mechanical systems where a threaded pipe end must be closed off. The 1-inch size fits standard NPT-threaded pipe and fittings. Typical applications include capping unused branch outlets, blanking off test ports, and closing temporary or future connection points during rough-in work.

Key Features

• 1-inch size fits standard threaded pipe and fittings
• Black iron construction for durability in piping systems
• Plain plug style for straightforward pipe-end termination
• Sold in a package of 10 units for job-site convenience
• Threaded design allows tool-free hand-start before final tightening

Compatibility

Designed as an OEM-style replacement fitting for 1-inch NPT threaded pipe assemblies in residential and commercial plumbing and gas piping systems.

Installation Notes

This plug is installed by licensed plumbers or pipefitters following applicable IPC and IFGC code requirements. Always shut off and depressurize the system before removing or installing any threaded fitting. Apply appropriate thread sealant or PTFE tape to the male threads before tightening. Use a pipe wrench or fitting wrench to achieve a proper seal without over-stressing the fitting.