【机械工程】由松散材料制成的非金属销子

ferrite core, material, non-metallic

adhesive-bonded dowel, non-metallic dowel made of loose material

non-metallic

non-metallic minerals【矿】

non-metallic material

thread, non-metallic

reduction of non-metallic coatings to metal

metallic surface coating, non-metallic