What this means
The IEEE assigned the MA-S block 8C1F64519 to SHENZHEN GW 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 8C:1F:64:51:9, it is SHENZHEN GW TECHNOLOGY CO.,LTD hardware.