The On/Off switch cycles through the three brightness settings for easy operation. The High setting provides an intense level 1250 daylight white lumens, with a run time of 2 hr. The Medium setting is a bright 600 lm, with a run time of 5 hr. The Low setting provides a very practical level of 300 lm for 9 hr. This is all made possible by the technologically advanced 10 W COB (Chips On Board) LED and the powerful Li-ion 2200 mAh battery pack, which is user replaceable. Three green LEDs are arranged in a bar graph format to indicate both the battery life and the charge level. The superior brightness levels are only part of the story; the beam pattern is important as well. The COB LEDs plus the unique "fresnel-like" lens creates an ultra wide floodlight beam - no rings, no shadows, no hot spots. The diameter to distance ratio is about 3:1, meaning for example, the beam diameter is about 9 ft wide when the light is 3 ft from an object. This industrial grade work light can light up a whole room, an engine bay, or a campsite, you name it. It is flexible, versatile and tough.