These replacement parts kit Compatible with Xiaomi Mi Mijia roborock Q7 / Q7+ / Q7 Max+ Robot Vacuum, This set works as great as the original ones, precision fit and easy install. These accessories made of environmentally friendly materials, To work on area rugs and sealed hard floors including hardwood, tile, marble, laminate and linoleum floor. The Replacement Part easy to replace without any tool. To keep your Household sweeping robot operating at peak performance, recommend to replace the kits every 3-6 months.according to the frequency of use, it can be replaced by a shorter or longer time.