i was thinking where i heard ascender and then you described how it worked i still couldnt remember where i used one..then you said your son a rock climber showed you..i remember now! rock climbers have alota neat tools and can do most anything with a rope...i went with a guy and he taught me enough to climb saftley...i was fascintated at how something that looks like a metal ring to me is really a device that if used properly lets me stay up there if i slip..all kinds of neat things...many can be used for tree stand saftey...thanx for the reminder i kinda forgot!