DC 12V 2A (24W) 4000mAh Super Rechargeable Protable Li-ion Lithium Battery DC12400 Blue

You tell me: This 12V 4000mAh battery hooked up to a string of LED lights that draw 12V 3.97A running at 76 lm/W efficacy lasted only ONE HOUR! One bloody hour.I set up a series of Energizer 8 AA 1.5V ( 12V in series ) 2500mAh that lasted TEN hours on the exact same LED light set up. And even at ten hours the batteries still had 70% charge remaining. This product had 60% charge remaining after one hour.I am profoundly disappointed in this crap product.

I Didn't Waste My Money

DO NOT ORDER! ! ! !Rating on battery pack isn't even close to actual rating. They used 3-1800 mah batteries in series which gives the whole battery pack a rating of 1800 mah. You would have to parallel the individual batteries to add amperage. The setup with the batteries and charger is a total fire hazard.

I did not like this at all..

This battery failed to charge. In fact, I'm not sure it IS a battery, it could be a hunk of toxic waste molded into a rectangular block and wrapped in cheesy blue plastic wrap. There is a tiny red light that comes on when it's plugged in. I went to return/refund, but Amazon doesn't want these things back physically due to the shipment/fire hazard issue. So they refunded my money and I have to take this thing to Toxic Waste for disposal. Hopefully Amazon will kick this crap off their site. Note to self: always read the reviews!Although the appalling translation in the "Instruction Manual" pamphlet was pretty entertaining.

used this for telescope power supply. took quite long to recharge. used occasionally but it died completely. did not get much use out of it. would not recommend.