Dia 10mm Polypropylene ( PP ) Solid Plastic Bearing Balls Precision Sphere Black. Material: PP (polypropylene). High resistance to chemicals, such as acids, alkalis, alcohol, many inorganic substances, salt solutions, solvents, gasoline, water, oil, grease, detergent, juice, milk, etc., but not resistant to aromatic hydrocarbons and chloric acid.
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