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Steel Adapter, 3/8-18 Female NPT To 9/16-18 Male SAE O-Ring Boss (Straight Thread O-Ring), Straight

Description & Features

The BRENNAN INDUSTRIES INC Steel Adapter efficiently connects a 3/8-18 Female NPT thread to a 9/16-18 Male SAE O-Ring Boss ensuring a secure and reliable fit for various industrial applications.

Constructed from high-quality steel this straight adapter offers durability and strength suitable for demanding environments. Its precise design guarantees a secure connection enhancing system integrity.

With a seamless transition from NPT to SAE O-Ring Boss threads this adapter is a reliable solution for connecting components with different thread standards. This product does not require a thread sealant simplifying installation and ensuring consistent performance.

This component is valuable for industries requiring robust and dependable threaded connections for hydraulic and pneumatic systems.

Supplier Part Number: 6405-06-06-O

Specifications

A 1.16	Alternate Part Numbers Alternate Part Number 621-1803, Alternate Part Number 6405-06-06, Alternate Part Number A2216-6-6S, Alternate Part Number C1BX45, Alternate Part Number MI-00316637, Alternate Part Number MINO-00028F64297	Brand Brennan Industries Inc	Brand Brennan Industries	Pack Size 1.00	UOM EA	Supplier Part Number 6405-06-06-O	Thread 1 3/8-18	Thread 2 9/16-18	Thread Sealant No	Product Weight 0.13 lbs

Similar Products

Model Number	Thread 1	Thread 2	A
2216-12-12S Female NPT To Male ORB Adapter	3/4-14	1-1/16-12	1.67
2216-16-16S Female NPT To Male ORB Adapter	1-11-1/2	1-5/16-12	1.91
2216-2-4S Female NPT To Male ORB Adapter	1/8-27	7/16-20	0.92
2216-8-8S Female NPT To Male ORB Adapter	1/2-14	3/4-16	1.65
6405-24-20-O Female NPT To Male ORB Adapter	1-1/4-11-1/2	1-7/8-12	2.12
2216-12-16S Female NPT To Male ORB Adapter	3/4-14	1-5/16-12	1
2216-16-20S Female NPT To Male ORB Adapter	1-11-1/2	1-5/8-12	1
2216-20-20S Female NPT To Male ORB Adapter	1-1/4-11-1/2	1-5/8-12	2
2216-24-24S Female NPT To Male ORB Adapter	1-1/2-11-1/2	1-7/8-12	2
2216-4-5S Female NPT To Male ORB Adapter	1/4-18	1/2-20	1.2
2216-4-6S Female NPT To Male ORB Adapter	1/4-18	9/16-18	1.24
2216-6-12S Female NPT To Male ORB Adapter	3/8-18	1-1/16-12	1.34
2216-6-8S Female NPT To Male ORB Adapter	3/8-18	3/4-16	1.25
2216-8-10S Female NPT To Male ORB Adapter	1/2-14	7/8-14	1.54
2216-8-12S Female NPT To Male ORB Adapter	1/2-14	1-1/16-12	1.72
6405-04-04-O Female NPT To Male ORB Adapter	1/4-18	7/16-20	1.16
6405-04-06-O Female NPT To Male ORB Adapter	3/8-18	7/16-20	1.21
6405-05-02-O Female NPT To Male ORB Adapter	1/8-27	1/2-20	0.94
6405-06-06-O Female NPT To Male ORB Adapter	3/8-18	9/16-18	1.16
6405-06-08-O Female NPT To Male ORB Adapter	1/2-14	9/16-18	1.4
6405-08-04-O Female NPT To Male ORB Adapter	1/4-18	3/4-16	1.16
6405-10-04-O Female NPT To Male ORB Adapter	1/4-18	7/8-14	0.81
6405-10-06-O Female NPT To Male ORB Adapter	3/8-18	7/8-14	1.55
6405-12-16-O Female NPT To Male ORB Adapter	1-11-1/2	1-1/16-12	1.91
6405-16-08-O Female NPT To Male ORB Adapter	1/2-14	1-5/16-12	1.61
6405-20-12-O Female NPT To Male ORB Adapter	3/4-14	1-5/8-12	1.19
6405-24-16-O Female NPT To Male ORB Adapter	1-11-1/2	1-7/8-12	1

Product Questions & Answers (1)

Question by: Gary R on Dec 22, 2025, 11:20 AM

got a fitting with a 3/8 NPT female port and need to hook up a SAE O-ring boss male line to it, this the right adapter for that?

Answer by: Customer Support on Dec 24, 2025, 6:22 AM

That's what this one's built for. One end is 3/8-18 female NPT and the other is 9/16-18 male SAE O-Ring Boss, so it bridges those two thread standards in a straight configuration. No thread sealant needed on the ORB side either, which keeps the install clean and straightforward.