It is composed of nylon, synthetic, or animal fur bristles of various diameters lined against a rather sturdy wire handle with a looped end for hanging.
[2] FDA grade brushes are designed to be resistant to acid and other corrosive chemicals, including aromatic and aliphatic hydrocarbons, ketones, ethyl acetate esters, and trichloroethylene.
[2] For example: Brushes are designed for the purpose of cleaning test tubes, therefore are developed to be able to reach all corners of the glassware.
It has an extra long radial bristle tip that is flexible enough to enter the narrow neck of various laboratory glassware, and fan out at the bottom of the chamber for efficient cleaning.
The middle section of the metal wire handle contains short stemmed bristles that can be used to scrub along the neck of the flask.