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Steel Adapter, 1-11-1/2 Male NPT Countersunk Hex Plug

Description & Features

The Steel Adapter 1-11-1/2 Male NPT Countersunk Hex Plug by Brennan Industries Inc exemplifies superior craftsmanship and durability. This adapter is designed for seamless integration in industrial environments where reliable and robust connectors are essential.

Crafted from high-quality steel this 1-11-1/2 NPT threaded adapter ensures a secure and tight fit minimizing the risk of leaks. The countersunk hex plug design facilitates easy installation and removal even in confined spaces.

Engineered for longevity this adapter is the ideal choice for professionals seeking a dependable solution for their connection needs. With no need for additional thread sealant it offers a straightforward and efficient installation process.

MPN: C1EH38

Supplier Part Number: 5406-HP-16

Specifications

A 0.77	Alternate Part Numbers Alternate Part Number 5406HHP-16, Alternate Part Number C1EH38, Alternate Part Number MI-00347851, Alternate Part Number MINO-00028F82906	B 0.63	Brand Brennan Industries Inc	Brand Brennan Industries	Pack Size 1.00	UOM EA	Supplier Part Number 5406-HP-16	Thread 1 1-11-1/2	Thread Sealant No	Product Weight 0.20 lbs

Similar Products

Model Number	Thread 1	A	B
2222-6S Steel NPT Socket Hex Plug	3/8-18	0.46	0.31
2222-8S Steel NPT Socket Hex Plug	1/2-14	0.61	0.38
2222-2S Steel NPT Socket Hex Plug	1/8-27	0.3	0.19
2222-4S Steel NPT Socket Hex Plug	1/4-18	0.46	0.25
5406-HP-12 Steel NPT Socket Hex Plug	3/4-14	0.62	0.56
5406-HP-16 Steel NPT Socket Hex Plug	1-11-1/2	0.77	0.63
5406-HP-20 Steel NPT Socket Hex Plug	1-1/4-11-1/2	0.83	0.75
5406-HP-24 Steel NPT Socket Hex Plug	1-1/2-11-1/2	0.83	1

Product Questions & Answers (2)

Question by: Randy W on Jul 27, 2025, 4:35 PM

Got a 1 inch NPT port that needs to be plugged off permanent-like. this the right size for that?

Answer by: Customer Support on Jul 29, 2025, 7:02 AM

A 1-11/2 NPT thread means 1 inch nominal pipe size with 11 and a half threads per inch, so yes, that matches a standard 1 inch NPT port. The countersunk hex design lets you seat it fully into the port using an Allen wrench, which keeps it flush and out of the way in tight spots.

Question by: Bonnie C on Jan 24, 2026, 12:06 PM

What size Allen wrench fits this plug?

Answer by: Customer Support on Jan 25, 2026, 9:42 PM

It takes a #16 Allen wrench to install or remove this countersunk hex plug.