Thrashin Supply EVO Billet Derby Cover Finish:Polished Corona stain is completely normal

Corona stain is completely normal and should not be mistaken for exhaust gas blow-by or broken seals inside the spark plug

2010-2013 Harley-Davidson Street Glide EFI FLHX - -

DOT approved

Black coated versions of the Industry leading polyurethane dampening kits

with a goal of keeping high cylinder pressure for optimum power throughout the entire RPM range

Thrashin Supply EVO Billet Derby Cover Finish:Polished Corona stain is completely normal3 Hole Design for Evo Engine Bikes Made in Los Angeles, CA Aircraft Grade 6061 Aluminum Hard Anodized Black or Hand Polished Available Comes with gasket Fits: 1998 Harley Davidson Road King Classic EFI FLHRC 1998 Harley Davidson Road Glide EFI FLTR 1998 Harley Davidson Road Glide FLTR 1997 1998 Harley Davidson Softail Heritage Springer FLSTS 1997 1998 Harley Davidson Softail Fat Boy FLSTF 1997 1998 Harley Davidson Softail Heritage Classic FLSTC 1997