The Lynx Levelers Recreational Vehicle Leveling Kit leveling blocks are modularly designed to not only configure to fit any leveling function, but also withstand tremendous weight. To use: simply set them into a pyramid shape to the desired height that the RV needs to be raised and drive onto the stack. The levelers can also be used as a support base for other stabilizing equipment. Use under single and dual wheels, under tandem axles and under jacks.