What this means
The IEEE assigned the MA-M block 200A0DE to HANGZHOU DANGBEI NETWORK TECH.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 20:0A:0D:E, it is HANGZHOU DANGBEI NETWORK TECH.Co.,Ltd hardware.