Quadratec Q9000 Synthetic Operator's Manual page 46

Pull of Last Resort: A Deep Buried Anchor Point
It is possible to be stuck in a spot where, although you
would want to winch there is no anchor point such as a
tree or large boulder. This is typical of getting stuck at a
beach or in the desert.
In this rare event, using a shovel, you must dig a
substantial hole to bury a large object secured with a
choker chain as an anchor point. Large objects to consider
may include an oversize spare tire, a large boulder or a
sizeable log. Simply put, the deeper you bury the object the
better the technique will work.
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