If you are have twins you dont need the anodes that stick down anyway, you can run the flat type anode that all Bravo's come with now adays. If you want to run them because you want more protection thats fine as well. There are 2 types of trim anodes. One type is for aluminum props, which is kinda thick and bold. The other is for stainless props, which is thinner and looks like half the thickness as the other. I dont even install the trim anodes anymore, I only install the flats on my customers boats.