Just FYI about the TK905 tracker
This is also the relevant link:
Two years ago I bought 6 'tk905's and they were Watch protocol. Last year I bought another 6, externally physically identical right down to the packaging, and they are Huabao protocol!
Both work perfectly well but trial and error is your friend when it comes to Chinese clones.
I want to share some information the tk905, although simple, was hard for me to find.
The protocol it uses is WATCH, and the port is 5093.
I hope this helps someone.