What type of parameters should have a function(a,b) to pass them directly to thread(a,b)?

I wanted to create special class ThreadVector to be able to push_back void class member functions to make them work concurrently. I tried to write the same parameters as thread has but got the error "Package options should be disclosed in this context". What type should parameters have?

class ThreadVector
{
    vector<thread> threads;
    template <class Fn, class... Args>
    void push_back(Fn&& fn, Args&&... args)
    {
        data.push_back(move(thread(fn, args)));         
    }
}
template<typename T>
class Class1
{
   void function();
}
ThreadVector threadVecrors;
threadVectors.push_back(&Class1<T>::function, this);