What this means
The IEEE assigned the MA-L block 00CBB4 to SHENZHEN ATEKO PHOTOELECTRICITY 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 00:CB:B4, it is SHENZHEN ATEKO PHOTOELECTRICITY CO.,LTD hardware.