Same Size Rotors Front and Rear?

check this pic out, its an AMG with the same size rotors (upgrade to another model spec) and look at the calipers. 4 piston up front and dual (if not single) piston out back and the pads for that caliper are postage stamp sized compared to the playing card sized pads for the fronts. Goes to show what percentage of the braking is up front (~80%) and whats going on out back.
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