Bryan used both 10 and 11 in his cues.
The easiest way to find out would be measure. If there is an inch of threads there just count them. If not...measure a half inch and count the threads times 2.
One is 11 threads per inch and the other is 10 threads per inch. This does not allow them to be interchangable. It is very easy to count the threads and figure out what you have.