Homer Simpson DUH!!! I forgot to mention the locking feature on these units!Thanks Ranger!This is why several references on any given subject are necessary.The other aspect of travel is KNOW YOUR AREA.The native bearers never deserted because of King Kong,but because they were out of their known turf.There are many natural indicators for direction also;check out recent issues of Wilderness Way magazine. Tritium illumination is needed only for military ops. so save your money.With the high end Silva units you employ a mirror,an extra signaling device.<br><br>