Textured surfaces can increase traction under wet and dry conditions to preven wheelchairs and other tools from slipping,thus protecting users' safet to a certain extent. There are some prefabricated holes behind the threshold bridge.You will need a drill bit to drill holes and then install the expansion screws included in the package to secure them. The bottom grid design maximizes the grip of the ramp and prevents the movement of the curb ramp.The force is uniform,with large bearing capacity and high stability. The car sidewalk ramp is suitable for families,supermarkets,factories,warehouses,schools,driveways,garages,loading docks,parking lots,shed entrances,etc. The ramp of the car is made of high-strength high-quality rubber with strong toughness,wear resistance and pressure resistance,which can be used for a long time