AC66U or AC66U B1?

[LarsErikOsterud]

How do I see if I have an AC66U or an AC66U B1?
And what is the difference between the two models?

 

[RMerlin]

The RT-AC66U_B1 will be clearly identified on its bottom label, and has non-detachable antennas.

It's basically the same hardware as an RT-AC68U but within a casing similar to the RT-AC66U.

 

[bbunge]

The B1 also has a front USB, dual core 1000 MHZ processor. Well worth the extra bucks!

 

[Mynpo]

LarsErikOsterud, I too had the same difficulty determining the difference. Mine was purchased brand new from Amazon was even labeled with 'B1' on the side of the box. I hijacked a thread and thanks to everyone I determined I was safe to flash.

This thread may further help: https://www.snbforums.com/threads/asus-rt-ac66u-find-out-hw-revision.36118/
In a nutshell though mine didn't have the USB3 port on the front, DID have detachable antennas, and on the stock firmware I could see I only had a single processor.