HD⚡SWITCH: Engineered Performance HIGH QUALITY: Precision Machined Accuracy IMPROVED DESIGN: Bore Sealant Coating Fills Imperfections For a Better Seal VERIFY FIT: Message Our Support Team Anytime Improved replacement for a better seal! Like most automotive seals, the HD Switch seals all use bore sealant material to fill any small scratches in the mounting surface. This makes for an extremely water and dirt tight seal.