: They provide a critical backup to the parking brake, which can fail if cables snap or if the vehicle is lifted.
placed under tires to "unblock" a vehicle stuck in mud, snow, or sand. Chemical Unblockers : Products like Harpic Drain Xpert used for standard household plumbing blockages. Are you interested in the culvert cleaning trick , or are you looking for a way to unstick a frozen wheel on a vehicle? tire unblocker
For best results, keep a valve-core tool and a small tire unblocker or compatible valve cleaner in your roadside kit. : They provide a critical backup to the