Busch & Müller Lumotec IQ2 Eyc Series Headlights
Great light. Funny name. Pronounced like Eisenhower's nickname.
The 50 lux beam is almost as bright as the Cyo (not the Cyo Premium, but the regular model) but the light is less expensive, smaller, and lighter. Without the mounting bracket the light weighs 2.5 ounces. And you can see how small it is in the pictures with the matchstick and hand included for scale.
In Senso mode "T" models like the Eyc detect the ambient lighting conditions and automatically switch between the daytime beam (optimized for daytime visibility) and the night-time primary headlight beam.