When upgrading from incandescent bulbs to LUMENS LED bulbs, many factory signal flashers will “hyperflash” (flash very quickly) due to the change in resistance from a standard bulb to LEDs. LUMENS LED Flasher relays are used in conjunction with LUMENS LED bulbs to slow the signal flash rate back to normal. If the vehicle has a signal relay, using these relays would be more cost-effective than installing resistors to maintain the flashing signal speed. Additionally, it is much easier to switch out a relay than to solder in multiple resistors in the vehicle.