I saw a product on TV awhile back that I'm hoping someone can help me locate. It is a hoop that bolts to the bottom of your extension ladder. Both ends of the hoop have feet on them. The hoop adjusts so that no matter what terrain you're on, whether it's level ground or a steep hill, the ladder will stand perfectly upright and stable. Anyone know what this ladder "tool" is called and where to buy it? Thanks!