I need an M2 B-key Wi-Fi module | No information on the h-node.org website

"Could you tell me whether the Wi-Fi module with an M2 B-key interface is single-band or dual-band?"

This question's unanswerable. The M.2 is just the physical connector shape. Knowing that provides no information about the radio. It's like knowing a light fixture uses a standard screw-in socket. That tells you the bulb will physically fit, but tells you absolutely nothing about whether the bulb is a dimmable LED, or what color it is.

"I recently discussed the Atheros AR9462 module"

This is the part you need. The AR9462 is dual-band.

"If I'm not mistaken, the Atheros AR9462 has an E key and an A key, but no B key"

That's because the A and E keys are standardly used for WiFi, while the B key is usually used for storage, and B-key WiFi cards are rare. Given the rarity, are you sure that your computer really does use that for the WiFi and has no available A or E key that could be used instead? If your computer really does use that, and there aren't any A or E slots to use instead, I would recommend getting an M.2 Key B to Key A+E Adapter and then using one of the standard WiFi cards.

Hello Jason,

Thank you so much for your reply and for being willing to help.
I hope I have enough money to cover your expenses )))

As for the Wi-Fi module with the B key, I agree with you—the E Key is often used, but modern single-board computers use this interface as a universal one, including for 4G modules, when the board has two M.2 interfaces or one M.2 and a second miniPCIe.

As for a 4G module for the M2 B Key, I've found a great option: the Sierra AirPrime EM7455 4G LTE (blob-free)

But I haven't been able to find a Wi-Fi module for the M2 B Key...