Garmin Varia HL 500 AUTOMATIC BEAM MODE - Based on speed information from an Edge, the headlight beam will adjust where the rider needs it the most -When deceleration is detected, the tail light will change its brightness to alert traffic that a cyclist is near and slowing. FOCUSED LIGHT - The Varia headlight focuses the light where you need it -on the road ahead. The headlight beam also has a high-beam cutoff to avoid blinding oncoming traffic while still shining up to 100 lux at 10 meters. AUTOMATIC LIGHT INTENSITY CONTROL - The brightness intensity of the headlight will adjust based on ambient light when paired with an Edge 1000.