So I just got the backing plate system for the flex just curious as to why the nut is a bigger size then the stock nut the stock Allen key doesn't fit it I wonder why they did that. Not a big problem I just don't want to buy a extra Allen key lol. Also I got 3 washers 1 regular small washer thick and 2 thin washers that are bigger what are those 2 for ? I love the plates I'm getting smaller pads soon 5" hybrid and the 6" fits my 7" megs pads perfect