Pro One TC88 Billet Derby Cover is CNC machined from solid Billet Aluminum, carefully polished, then show-chrome plated to perfection! Chrome hardware included. Fits 1999 to 2012 Harley-Davidson TC88 motors. NOTE: '06 and later Dyna and '07 and later Softail and Touring applications require a gasket to be purchased separately as your original Derby Cover will have an o-ring. They are available under Harley-Davidson OEM part number 25416-99C or Drag Specialties part number 0934-0289 or 0934-0788.