What this means
The IEEE assigned the MA-L block C46E7B to SHENZHEN RF-LINK TECHNOLOGY CO.,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 C4:6E:7B, it is SHENZHEN RF-LINK TECHNOLOGY CO.,LTD. hardware.