The Wuben B2 is a 21700-powered bike light. Far too many bike lights on the market use non-removable batteries, making them disposable when the battery wears out and making spare batteries impossible. The B2’s use of a 21700 is enough by itself to stand out in the field. Its mount accommodates a variety of handlebars, and its efficient driver provides stable output in lower modes for a long time. The mount is reasonably secure, but it’s important to press the light in firmly until it clicks, or it may fall, evidence of which is visible in some of the photos.
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