The lights are very good, with a strong enough light to be visible effectively at night. The rear (red light) turns on both around and in the round lamp in the middle, to make the illumination more intense. The front light, if you tighten it too much on the handlebar with the screw, the pressure can open the top part (where the battery goes), so you should only tighten it until it doesn't move. Although they seem to have a sturdy construction, I haven't tested them on a dirt road yet to see if the plastic parts open (the points where the batteries go).