About Signaling: Signaling is a form of communication, and often overlooked. If you do encounter an emergency situation, a simple signaling device can often stop that situation from getting worse.
Take as an example, a simple backpacking trip with friends. You're at camp enjoying the evening and go out to get some firewood. The sun is setting and you find yourself disoriented in the dimming light - which way was camp? You know you're close, but which direction? A simple whistle can alert your friends, who can signal back and now you've got a direction to go. Problem solved, never really becoming an issue.
You're walking along a ravine, and you slip and slide down the side breaking your ankle. You can't very well climb back up without causing more damage, and you can't go down that dropoff to the rushing river below. There are hikers periodically along the trail above, but they can't see you, you're below the ledge a mere 30 feet below them and they'll look right over you as they enjoy the view of the ravine. Again, as you hear a group of hikers above, you can get their attention with a simple whistle - and get help.
We think communications should be a key element of your kit. Communications/Signaling can take many forms; Land to Land, Land to Air, Short and Long Range and Visible or Audible.