What devices use 004003?

Any network device with a MAC address starting 00:40:03 was manufactured by or for Emerson Process Management Power & Water Solutions, Inc..

MA-L · OUI prefix

Emerson Process Management Power & Water Solutions, Inc.

Q: Who owns MAC prefix 004003?

004003 is registered to Emerson Process Management Power & Water Solutions, Inc. in the IEEE MA-L registry.

Any MAC address starting 00:40:03 is registered to Emerson Process Management Power & Water Solutions, Inc. in US.

OUI prefix	004003
Vendor	Emerson Process Management Power & Water Solutions, Inc.
Registry	MA-L (24-bit, large block)
Country	US
Example MAC	00:40:03:00:00:00

What this means

The IEEE assigned the MA-L block 004003 to Emerson Process Management Power & Water Solutions, Inc.. Every network interface they manufacture under this block has a MAC address beginning with these digits, followed by a unique per-device identifier. If a device on your network shows a MAC starting 00:40:03, it is Emerson Process Management Power & Water Solutions, Inc. hardware.

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