Moen Monticello Towel Bar What Size Bolt Do I Need For A Moen Multi-function Shower Knob For Temperature & Volume?

What size bolt do i need for a moen multi-function shower knob for temperature & volume? - moen monticello towel bar

I bought a Moen Monticello 3320, but the screws seem to have lost her the knob to the temperature and volume of what I need to adjust size manipulated to come? Lets get management and the volume! Can not be derailed! I would appreciate any help here!