Now there is no need to cut or splice wires in order to install a headlight modulator on your bike! With the Plug & Play Headlight Module, simply select which harness is needed for your bike, then plug it all together Note: Harness' sold separately Toggle Modulation ON and OFF: The modulation of the headlight can be toggled on and off by the user at any time Auto Night Shut-Off: The Diamond Star Headlight Modulator is designed to automatically turn on and off at specific light levels in order to comply with the DOT's regulation of no night time modulation To Switch From Max to Min Mode: The Diamond Star Headlight Module is equipped with two levels of modulation to meet your visibility requirements. (Both are fully DOT compliant). Heads Up Alert : The Diamond Star Headlight Module can be connected to your bikes horn wire in order to add a visual alert to your horn's audible alert Please Note: as per D.O.T. regulations, the Heads Up Alert feature DOES NOT work at night Emergency Headlight Feature: The Diamond Star Headlight Module is constantly monitoring the bulb that you have selected (high beam or low beam). In the event the bulb(s) should fail; the alternate bulb(s) will instantly be turned on No Excessive Heat Build-Up: Handles high power demand sealed beam and halogen headlights totaling up to 130 watts! Operates efficiently with only slight increase above ambient temperature at continuous max headlight power rating Surge Protected: Internal protection against transient voltage spikes during engine starts or charging system operation. Also drops out if voltage is too low, avoiding problems associated with low voltage Compact Size - 2-1/4" long x 1-5/8" wide x 5/8" high Weather Resistant Heat Sink Case Requires purchase of Signal Dynamics Corporation Plug and Play Harness Adapter: Single H4 445-957, Dual H4 445-958 or Universal 445-960 to complete install