Non-slip Design: There is a non-slip with precise gearwheel mesh system on the surface of levelers,preventing camper tire from sliding. Rubber mats help increase friction to prevent levelers sliding on mats HDPE Material: We select high-quality HDPE, it is harder and makes longer life. It accommodates vehicles up to 35000 lbs with tires up to 32" in diameter Fits Dual Axle Trailers: Features a perfectly sized design that fits most dual axle trailers without modification. Achieve a fast, effortless setup right out of the box. Effortless to Level Your RV: Place the anti-slip mat, drive up the curved leveler and stop at the height you want to achieve, and lock the wheel with the chocks Portable Camper Leveler Kit: Including two curved levelers, two chocks, two black rubber grip mats. The kit all in Oxford fabric storage bag,Easily store and carry.