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200mAh lithium-ion battery (front light) and 500mAh lithium-ion battery (tail light), Waterproof rating is IPX5, runs for more than 2 hours at the highest setting
Aliexpress
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Price history and price alert
Price history (for all/most countries) for Utorch USB Front Rear Bicycle Light is here.
Price records source(s): Gearbest
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You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).