MC5a brake drum size

[Lin]

I was trying to figure which Centramatic balancer would fit my 11r 22.5 tire.  Apparently there are two different possibilities--one of which specifies it is to go over a 16.5 inch brake drum, the other says fits trucks motorhomes and coaches.  Does anyone know which one is right?

[TomC]

Most buses will have 15" brakes in front.  I have 14.5" brakes all around-7" wide in front and 10" wide in back. Good Luck, TomC