ESP SYSTEMS, LLC

Any device whose MAC address begins with 00:21:EB has a network interface built by ESP SYSTEMS, LLC. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

00:21:EB

Organization

ESP SYSTEMS, LLC

Address

1422 East Fourth Street Charlotte NC US 28204

Source

IEEE OUI registry

Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.