A test tube brush is used to easily clean the inside of a test tube.
Test tube brush=use for cleaning test tubes
It is a device, made with nylon bristles attached to a twisted-wire shaft, used to knock the bottoms out of test tubes. Or at least it was when I was in high school chem class. It is a brush that is...
it is used for cleaning the testube.
Um... to clean test tubes! Test tubes are used very often to perform experiments on a small scale, hence they need to be cleaned quite often.
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