1/4" Thick Solid Billet Aluminum - Will never crack like cheap die cast covers. Smooth Radiused Edge Shifter Sleeve hole does not damage O-ring when being installed. Stainless Steel washers recessed into cover so aluminum will never gouge. Fits: LATE 1984 - Up FXR Note for 1984 bikes: Compare the shape of your cover to ours. Early year bikes have a different shape.