The stock alternator cover on the engine has a cover plate on it. There are two reasons for replacing the cover plate. First, because it is dingy and looks like crap. Second, the bolts securing the cover plate are often over-torqued from the factory and the small 3mm allen-headed bolts strip. Should the bolts strip, they must be slotted with a dremel tool and pounded out with an impact driver. This often mars the stock cover plate. This replacement cover plate looks the business, and is cut from billet 6000 series aluminum, slotted with an attractive pattern and then anodized. Included are 2 replacement bolts. Use the O-ring from your stock plate. The plate comes in two variants – one for early Ducatis and one for the DS1000/DS1100 Engine. Look at the shape to determine yours.