This nylon cleaning brush features a fan-shaped end and measures 15 inches in total length. It is designed to clean test tubes and other narrow glassware with inner diameters of approximately 1.6 inches. The twisted stainless steel wire handle provides durability and flexibility. The nylon bristles effectively remove residue without scratching glass surfaces, and the fan-shaped tip helps reach the bottom of round-bottom vessels. Suitable for routine laboratory glassware cleaning.