What this means
The IEEE assigned the MA-S block 8C1F643F7 to Mitsubishi Electric India Pvt. Ltd.. 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 8C:1F:64:3F:7, it is Mitsubishi Electric India Pvt. Ltd. hardware.