What this means
The IEEE assigned the MA-M block 04585D2 to Foxconn Brasil Industria e Comercio Ltda. 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 04:58:5D:2, it is Foxconn Brasil Industria e Comercio Ltda hardware.