The dual switch system in the side can realize a fast selection between four different brightness levels and tow various flashing functions. Featuring a max 800 lumens output and the over ten days ultra long runtime, the light can meet your illuminating needs unconditionally. In the meanwhile, the unique design makes the TK41 much more compact and lightweight. With the perfect combination of the outstanding performance and the enjoyment of using it, the TK41 is the dependable partner when outdoors searching, caving or using as a spare light for automobiles, etc.