1. Please pay attention that there are limits on painted walls, otherwise it might damaged your paint. Avoid using on uneven surface, the more smooth the wall, the better the results. 2.This screw can hold up to 10kg. But we'd like to suggest no more than 10kg for holding a long time. 3. Please clean the adhesive surface with water if it has dust covered before installation the hook. 4. Do not use it at temperatures above 80 degrees.