Extender bars are useful when you are really stuck and need additional grip. If your truck is dug in very deep and essentially stuck on high center extender bars can also help get you out. Laying a log or tree limb parallel to the tire and then having the extender bar come down on it slowly can lift you out. Extender bars are intended for use when stuck in deep mud or even sand. We do not recommend use in the snow as it is possible that the extender bar can come loose from the cleat and get lost in deep snow! We strongly advise ONLY using extender bars on your rear drive wheels so there are no issues with clearance. To use your extender bars you simply slide them into the traction cleat until they are stopped by the pre-installed set screws.