Update 20.05.2024
The headlamp continues to perform perfectly, even after almost daily use in evening training sessions. In a recent race (Apr. 2024), starting at 17:00, I needed the headlamp from 20:00 until 06:00+ the next day. I took the headlamp out of my belt to wear it and found that it was on (the power button was accidentally pressed), at an intermediate brightness level. I don't know how many hours it was on before. I know that I finished the race without the headlamp's battery running out. Quiet and safe.
So, pay attention to its "storage" to avoid the anxiety of accidentally turning it on.
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Initial assessment.
The VARTA H30R headlamp was purchased to be worn on an ultra marathon route. Literally, due to its small weight (47gr), there was no discomfort on the head, even after 7 continuous hours of use. It did not move from its position, nor did it irritate the forehead.
The battery life is incredible. At the low setting, it remains on without the brightness decreasing at all, for 21+ full hours! It is worth noting that the brightness of the low setting is very satisfactory for running in the mountains or in complete darkness, as its range and beam angle/focus easily cover the road. You run smoothly.
It is a headlamp that outperforms many well-known and more expensive ones.
I would definitely buy it again and recommend it without any reservations. The definition of value for money, without compromising on performance and quality.