Lithium batteries feature a long life, and excel in extreme cold, but are expensive. Bulbs come in a variety of shapes, sizes, light intensities, power-draining properties and prices. Krypton and halogen bulbs provide more intense beams than standard bulbs, but also drain more power from the batteries. Activities such as mountaineering or diving require an intense beam. But for the average user, perhaps the most important considerations are availability and price.
Some lights feature as an option a rubber tab for that purpose.
Lanyards , standard on some models, come in handy for hanging from a tree or from the light loops on the ceiling of a tent. Some lights come with adjustable beams , narrowing and brightening for use during specifics tasks, such as locating a specific spot on a map at night. Always carry extra batteries and bulbs when in the back country. However, ni-cad batteries can be used in place of the standard alkaline.