Private / randomised address device on my network
This is not a manufacturer: it is a private, randomly generated Wi-Fi address that phones, tablets and computers create for each network to protect your privacy.
What Private / randomised address makes
iPhones and iPads (Private Wi-Fi Address), Android phones (randomised MAC), Macs and Windows laptops (random hardware addresses) generate a separate address per network. These addresses have the locally administered bit set, so the second hex digit is always 2, 6, A or E (for example x2, x6, xA or xE in the first pair). They are not registered to any company, which is why no manufacturer name appears.
What the device on your network probably is
Almost certainly a phone, tablet, smartwatch or laptop. On a home network it is usually a family member's or visitor's phone.
How to work out which device it is
On an iPhone, open Settings, Wi-Fi, tap the info button next to the network, and compare the Wi-Fi Address shown with Private Wi-Fi Address turned on. On Android, open the network's details in Wi-Fi settings; on Windows and Mac, check the Wi-Fi network's properties. The hostname in your router list, often the phone's name, usually settles it.
Should you be worried
Nothing to worry about in itself: this is the privacy feature working. It does mean the address cannot tell you the brand, so match it by device name or by checking each phone and laptop.
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