We learned about such a "thing" for grinding by accident. In fact, this is just a small sponge, like those used to wash dishes, "drenched" in some kind of substance resembling sandpaper. There are soft, hard and medium blocks - of course, it depends on the "grain" of the sponge's emery wrapper. Here is the appearance taken - it looks like a box, only a big one. On both sides - from the ends - sponge "as it is", without sandpaper. As it turned out, grinding with such a "device" is very easy. they used to suffer - they nailed sandpaper to a wooden bar, now it's superfluous. Due to the fact that it is still a sponge, the grinding block can be squeezed, waited, sanded in narrow places, very convenient. The work goes quickly. In the store, a grinding block costs 36 rubles, in the Internet store you can "take" 23.
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