What this means
The IEEE assigned the MA-L block FC455F to JIANGXI SHANSHUI OPTOELECTRONIC 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 FC:45:5F, it is JIANGXI SHANSHUI OPTOELECTRONIC TECHNOLOGY CO.,LTD hardware.