In the practice of the house master there is often a need in a small brush for cleaning small parts, corrugated surfaces, plates or printed circuit boards. Very convenient for this purpose, a regular toothbrush. It is only necessary to change (as shown in rience the configuration of its handles, heating over the flame of a gas stove or in boiling water. E. SAWICKI, g Korosten, Zhytomyr region.
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