If you have two or more turn signal filaments on each side of your car, you can add the STS-3 Sequencer Kit and really indicate your intentions.These modules feature sophisticated electronics that automatically adjust the sequencing speed to match the turn signal flasher in your car. While other products offer you fixed timing or complicated manual adjustments, our modules sense your car's flasher speed and adjust the 1-2-3 sequence timing for you. Want more separation between individual lamps? Just put in a slower flasher!If your car has combination stop/turn signal lamps, these modules will sequence the turn and emergency flashers only. The brake lights operate normally! However, if you also want a single brake light sequence (called "brake light burst"), these modules will do it. Your Choice!Each kit comes with 2 modules (one for each side of the car), wire, connectors and printed instructions. Installation takes about an hour, and for most cars, only basic hand tools are required!Note: Sequential Turn Signals only work on cars with combination brake/turn signal lamps. They will not work on cars with separate turn signals or cars with amber lenses.