Gemini 110 to 1000 lm Bicycle Headlights
About Gemini - "Gemini Lights is our concept of what proper illumination gear should be. We cherish the great moments spent outdoors with our friends and family. Capturing nature's fresh air and immersing ourselves in scenic surroundings is what we seek. Whether your outdoors is a sprawling urban city, or a densely forested landscape, we help you stay sure-footed with world-class illumination."
A lumen is a measure of the total "amount" of visible light emitted by a source. The higher the lumen rating, the brighter the light.