Front turn signals follow the same generational split as fog lights: 2015-17 uses a standalone LED turn signal, while 2018-23 combines the turn signal with the fog light in one sequential LED unit. Rear side markers are simpler, the same LED kits fit the full 2015-2023 range regardless of generation. Not sure which front turn signal matches your Mustang? Our S550 lighting specialists can help you confirm before you order. While upgrading or restoring your S550 turn signals and side markers, finish up the job with upgraded 2015-2023 Mustang headlights or 2015-2023 Mustang taillights. Shop our full selection of S550 Mustang Lighting to get your Mustang looking better than ever!