The nut is for the front axle of the mad mod fits all years produced. 

Please note this nut is made of plastic instead of the original aluminum piece, but works just the same. 

The thicker part of the nut gets inserted inside of the fork before putting the through axle through the hub. this only has to go in snug do not over tighten. 

Color is a matte black instead of the original gloss black.