ADD-Engineering BV

Any device whose MAC address begins with 28:F5:32 has a network interface built by ADD-Engineering BV. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

28:F5:32

Organization

ADD-Engineering BV

Address

P.O. BOX 5893 ROTTERDAM ZH NL 3008 AW

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.