I reread the title and it asked what is the top tool. No where did it say the only tool... As a matter of course, any vehicle I drive anywhere has an air compressor, shovel, jack, snatch strap, extra fuel, extra water, a change of clothes, blanket and cell phone (all but useless in 90 percent of Canada north of 600km of the southern border as I have discovered). Only the Mercedes has a 12,000 pound Warn winch but it is disintegrating due to lack of use. The traction boards get periodic use and I like them. Most World travelers also have everything but the Winch in their kit.