Uncompromising headlamp for extreme use in mountain biking, orienteering, and caving. With 1100 lumens, the Duo S offers extremely high brightness. It is waterproof up to 1 meter for about 30 minutes, battery-operated, and extremely robust. Therefore, it is ideal for demanding outdoor sports (caving, orienteering, biking, etc.). To avoid blinding others, the Duo S is equipped with Petzl's patented Face2Face anti-glare feature, making group movement more comfortable. Depending on the need, users have five lighting modes available. These range from a wide beam with low brightness and long duration to a boost mode for short-term access to the maximum brightness of 1100 lumens. The lamp features a large, ergonomic switch that can be easily operated even with gloves. An electronic lock prevents accidental activation during transport and when the lamp is not in use. The battery housing worn at the back of the head creates a balanced weight distribution. When the battery is nearly depleted after a long trip, the Duo S automatically switches to reserve mode. In Constant Lighting headlamps, the brightness remains consistent throughout the specified lighting duration. This brightness is below the maximum value when the lamp is turned on. After the lighting duration ends, the lamp automatically switches to reserve mode with reduced brightness.