Good evening everyone 
I am not going to sell those particular devices but at the same time want to say that I discovered this experience like very fascinating - ability to keep your crypto universe in your hands ( in a safely and securely manner, I hope ).
So my assumption that is as a user I may want to see additional tab in the extension which allows to me usage of my plug-gable hardware devices as additional option. This experience could be represented like UI flow (again don’t sell it but for instance https://www.myetherwallet.com/access-my-wallet):
access-my-wallet → choose between available deveices → connect device → switch extension window into hardware sign mode
There are few resources with available API: