With one button switch and 3 modes: 2 LEDs on，battery life can be up to 200 hours; 4 LEDs on， battery life can be up to 80 hours; 8 LEDs on，battery life can be up to 20 hoursLight bulb type: White LEDAdjustable elsastic head strap Adjustable inclinationWith a head strap， be convinient to use it even when you take bike or climbing， also be suitable for a emergency light Color:Grey ; black Power by 3 AAA battery( battery is not included )