Eaton FF4177-16S Square Head Pipe Plug 1 Inch Mnpt

Product Description

The EATON FF4177-16S is a square head pipe plug designed to seal threaded pipe openings in industrial and commercial plumbing, HVAC, and mechanical systems. Manufactured from steel, this straight-body plug features a 1-inch male MNPT thread for secure, leak-resistant closure of pipe ends, tees, crosses, and other fittings. The square drive head allows installation and removal with a standard wrench or socket. It is rated for a working temperature range of -40 degrees F to 250 degrees F, making it suitable for hot and cold service lines encountered in typical mechanical system work.

This plug is used wherever a threaded pipe port needs to be capped or blanked off during installation, maintenance, or system modification. Common applications include sealing unused ports on pipe manifolds, capping test ports, and plugging open tees during phased construction or repair work. It is appropriate for plumbing, hydronic heating, compressed air, and similar low-to-moderate pressure piping systems handled by licensed plumbers and pipefitters.

Key Features

• 1-inch MNPT male thread for direct engagement with standard NPT female fittings
• Square head drive allows use of a wrench or socket for installation and removal
• Steel construction provides durability in mechanical and industrial environments
• Rated from -40 degrees F to 250 degrees F for broad service temperature coverage
• Straight fitting shape for straightforward port sealing without offset or transition

Compatibility

Designed as an OEM-style replacement or stock fitting for use in standard 1-inch MNPT female-threaded pipe ports across industrial and commercial piping systems.

Installation Notes

Installation is performed by licensed plumbers or pipefitters following applicable IPC and IFGC guidelines. De-pressurize and isolate the system section before installing or removing any pipe plug. Apply appropriate thread sealant or PTFE tape to the male threads before engagement. Do not overtighten steel plugs into cast fittings, as this may crack the female fitting body.