Filler combination polyether is a polyether polyol composite system used for filling purposes. It mainly contains polyether polyols, blowing agents, catalysts, flame retardants (added according to specific needs) and other components. Polyether polyols are the main building blocks that provide the basic skeleton structure for the final filler material. Its type and molecular weight will vary depending on the filling requirements. For example, high-viscosity polyether polyols help form a more stable filling structure. The blowing agent can be a physical blowing agent (such as alkanes with a low boiling point) or a chemical blowing agent (such as water, etc.), and its main role is to produce gas during the reaction process to make the filler material foam, thereby increasing the volume and reducing the density to a certain extent. Catalysts are used to control the speed of foaming and gelling reactions to ensure that the reaction proceeds as intended. If it is used in some occasions with fire protection requirements, the addition of flame retardant can improve the flame retardant performance of the filler material.