Have you ever tried to change the tire on an RV or multi-axle trailer? The Rapid Jack is your best friend when it comes to fixing a flat tire or removing a wheel on your multi-axle trailer or dually truck. Simply place the small end of the Rapid Jack under the closest good tire and drive up! NOTHING COULD BE EASIER! It can also be used as a jack wheel holder, a jack post block, and a pad block (see pics). Doubles as a wheel chock. It's the FASTEST jack around ...we call it 'Rapid' for a reason!