... the changes of external conditionas.thus to make the transducer always work in the best resonance.Higher efficiency. 5. Widely used ... Application: Shaping and polishing all kinds of complicated mold (including hard alloy mold), mold cavity, narrow groove, blind hole, corner, ... into lens face. 2.Polishing material: Various kinds of metal, hard alloy, glass, malachite and agate, etc. 3.Surface roughness: ...