MA-M: a /28 block, one IEEE assigns within a larger OUI when a full /24 isn't needed, covering 1,048,576 addresses.
PrefixA4:4F:3E:00:00:00 /28
Vendor addressNo.555 Rongqiao Road,Pudong district, Shanghai,China Shanghai CN 201206
Country🇨🇳 China
RegisteredApr 20, 2026
Block rangeA4:4F:3E:00:00:00– A4:4F:3E:0F:FF:FF
Address capacity1,048,576
AdministrationUniversally administered: its prefix comes from a block registered through the IEEE Registration Authority
TransmissionUnicast: addressed to a single device
SourceIEEE Registration Authority
Address capacity is the size of this registered block, not a count of devices actually manufactured or online. Registration identifies the organization holding the block, not a specific device model or unit.
Curious how a prefix like this turns into a full address? See how MAC addresses are structured →
Example addresses in this block
Where this block sits
The nearest registered blocks of the same size on either side of this one in IEEE's address space.
United Automotive Electronic Systems Co.,Ltd holds 2 registered blocks in the IEEE registry, ranking #3,330 of 33,427 organizations by block count.