WhatsApp Channels are pre-activated WhatsApp Numbers that are used by several WhatsApp marketing tools, scripts, software, and several other solutions that allow you to automate any kind of WhatsApp marketing promotions & marketing activities.
Now, since these are the mobile numbers that will be used by any kind of desktop or web based application you will use. You have an option to either get these numbers virtually or convert your real SIM card numbers into a WhatsApp channel.
After doing a bit of research, I found that there are two kinds of WhatsApp channels.
Protected WhatsApp Channels vs Unprotected WhatsApp Channels.
I don't want to re-phrase what's already been written about them. You can check the link above with more information on it.
Here's a list of places I found where you can purchase WhatsApp channels with highest quality of vendors who provide bulk WhatsApp channel registration services.
This company seem to be providing only Chinese WhatsApp channels as of now.
This company provides channels from various different countries, like:
Indian WhatsApp Channels (India based local SIM Card activated numbers)
Russian WhatsApp Channels (These can be virtual as well as real SIM channels)
UK WhatsApp Channels (UK Based WhatsApp numbers)
USA WhatsApp Channels (+1 series WhatsApp numbers)
There are other places also where you can purchase bulk WhatsApp channels:
WhatsApp Software (Found them very very expensive, comparetively to all companies!)
Also,
Please don't forget to look into my list of WhatsApp marketing software, tools, scripts, solutions and panels here.