When upgrading light bulbs from incandescent bulbs to LUMENS LED bulbs, many factory signal flashers will "hyperflash" (blink very rapidly) 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 speed 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.