I'M SPA

Any device whose MAC address begins with 20:91:D9 has a network interface built by I'M SPA. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

20:91:D9

Organization

I'M SPA

Address

VIA BIRON 102/3 MONTEVIALE VICENZA IT 36050

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.