What this means
The IEEE assigned the MA-M block 646266E to Shenzhen Jie Shi Lian Industrial 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 64:62:66:E, it is Shenzhen Jie Shi Lian Industrial Co., LTD hardware.