What this means
The IEEE assigned the MA-L block 7404F0 to Mobiwire Mobiles (NingBo) 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 74:04:F0, it is Mobiwire Mobiles (NingBo) Co., LTD hardware.