1 of 1 people found the following review helpful.

GARBAGE!!

If I could give it less than one I would, thing won’t even start a lawn mower battery, and customer service is maybe worse than the product!! After being told that the product wasn’t doing what I actually saw it doing they said it can’t be what’s going on!! Lawn mower batter reading 10V hooked the GB 40 up it went to bypass mode them wouldn’t start the battery after 2 tries. Checked the GB40 and it was completely dead!! After bickering with Customer service I decided to cut my losses as a lesson learned. Figured I would charge my IPhone with it by the pool. After hooking my iPhone up at 20% and the GB40 at full charge I went back about an hour later and saw the GB40 had charged my iPhone to 55% and the GB40 was almost dead!!