eBay has plenty of these usb 4G dongles going for next to nothing, so I thought I’d get one, primarily to see if it would work in my DrayTek router.
It turns out it’s a badged Huawei E3372h, which fortunately is supported by latest DrayTek routers. It doesn’t seem to be running a special firmware. When you plug it into a PC/Mac it just installs a an ‘internet connection sharing device’ and loads up a web page in your default browser, showing the status.
I tried an O2 sim in it and it asked for an unlock code, so EE sims only
They’re a bargain at £5 especially if you have a newer DrayTek router.