Ball-type sticking pulley, free rotation and flexible, unlimited sliding. You just need paste the universal wheel on the bottom of the box, then the heavy box can be easily moved, and the silent wheels are stable and quiet, will not scratch the ground, which is not easy to shake when pushing. It can easily move heavy objects without stress. Features - Material: PP. - Size: 4.00X4.00X1.50cm/1.57X1.57X0.59inch. - Manufactured with PP material, with excellent durability and practicality. - Fine workmanship, smooth edges, no burrs, and very friendly to the skin of your hands. - The casters can be pasted on the bottom of the storage box, making the movement more labor-saving and convenient. - It has good carrying capacity and will not be easily , can use it with confidence. - Very suitable for makeup storage case, kitchen, table, bedroom, bathroom, living room and flower shelf. Package list: 8 x sticky flexible wheels