Battery charger for 18650 (model#2019006900)

This charger appears to work fine, but it would be GREAT if there was a guide in Osoyoo Robot car starter kit to tell you what the colors on charger mean. The charger started out green with no batteries in it, instantly changed red when batteries were inserted, and then continued to change color throughout the process of charging. from red, to orange, to yellow, and then green, with every color in-between. you kind of just have to wait until the color looks like it has not changed shades of green in a while, and then you know it is charged, but I've never seen a charger work like that before.

The only info I could find online about chargers for 18650 li-ion batteries was at a laser pointer forum, and it seems like this kind of charger has to discharge the battery in order to display a color, which is based on the voltage of the battery.

That would explain why it is constantly changing color, but seriously, even one small piece of paper saying how the charger works and what the colors mean would be wonderful. Overall it appears the product is working very well, so I give it a 8/10, all things considered.