Headlamps are not a necessary item and I only use them in larger survival kits. However, they are very handy when an activity requires the use of both your hands. For smaller kits, I usually carry one of those elastic straps that have a small loop sewed onto it. I can place one of my small lights into the loop and place the elastic loop around my head. It leaves my hands in free.
For larger kits, you may want to include a headlamp specifically designed for this purpose. Again, there are many choices. I use LED headlamps, as they burn longer than the AA-battery type.
My choice for medium to large kits, it has three LEDs and operates on three AAA batteries with a burn time of 150 hours. It is small and light and packs well. It has four LEDs with switch that allows you to use it in economy mode (400 hours), optimum mode (120 hours) or maximum mode (80 hours). The fourth option allows for a blinking, intermittent mode (400 hours). It is essentially the same size as the original LED headlamps, expect for being slightly thicker to accommodate a new bracket that allows the LED headlamp to be titled down.
