Drains batteries even when off

I installed one of these with new batteries in the spot where I needed light. It was very easy to install, and gave me great light for a couple of minutes (which is all I needed). I turned it off right away. I used it again for brief spells for the next two days. By then the light had noticeably dimmed. So tried leaving it off for two days. At that point it didn't go on at all. My conclusion is that it drains the batteries even when not turned on. I returned them for a refund.

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