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

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

Product Questions & Answers 2

Product Questions & Answers

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

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

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.

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

What size Allen wrench fits this plug?

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

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

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

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