Even 1 LED has the necessary minimum light intensity. During the day it is a bit of use every night with leaving it outdoors while being attached to the bicycle, but light intensity is stable without becoming dark. Automatic ON-OFF also works well. It is still 1 week after using it, but no complaint at the moment.
I have a road and cross. For the safety of the night and searching for items that will automatically turn on when entering the tunnel we arrived at the light here. I do not know the durability, but the size is satisfied with the allowable range size.
There was no problem with the seat post regarding installation. The operation was as described. It may be slightly dark. I thought that it was a bit brighter. I do not even think that this is the limit in capacitors.
I attached it under the saddle, but because it is outdoor storage bicycle, it seems to be able to charge. It also looks good from afar, so it will light up when it gets dim. At the beginning of use, we removed the light itself and charged it for about half a day under direct sunlight. It is very easy to use and good product.