Double disc single speed metallographic sample pre mill M-2 is a wet grinder, it USES the different size of the metallographic sandpaper, on a variety of metal and alloy samples.

双盘单速金相试样预磨机m - 2是一种湿式磨光机，它利用不同粒度的金相砂纸，对各种金属及合金的试样进行磨光。

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The rest of the price difference is accounted for by the psychological impact of a higher price on a typical British buyer who would mistake nought-grade sandpaper for luxury as long as it were priced high enough or offered in a variety of colours.

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