One of the batteries was DOA. Unfortunately, I didn't notice this until I actually put the battery in the camera, which was after the return time window.When I put the battery in the charger, the red light comes on like normal indicating it's low and charging. I never stood there and watched it until the battery didn't work. After I found out the battery didn't work, I watched the charger after I put the battery in it. After putting the battery in the charger, within about 15 seconds, the chargeSee full review