Hi everyone,
I have just purchased a B/H emperor !
There are no markings/logo usually on bell and top joint
All I know is it is a B/H this by the pivot screw design
But after that I am lost,  how do I know whether it is an emperor or one of the other many models regent etc. manufactured by Boosey and Hawkes.

If anyone could help I would be very grateful

Many thanks. Kaytee73.   First time of asking a question