It has two parts: cleaning and de-stoning: 
Cleaning part removes all materials that deviates from the size of the grain  kernel like straw, strings, small seeds which are light and effectively  extracted by sieving.
De-stoning is mainly to remove any additional stones.
Efficient cleaning, high output, easy operation, good appearance, stable  performance, low consumption, light weight, low noise and no dust pollution. 
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