Excellent set of cleaning brushes. used in technical repairs. Includes a brush with plastic bristles. A brush with steel bristles. A brush with brass bristles. 1/4" hex shank at the end. which can be attached to a composite handle. Also included is a 150mm extension with quick release. Can also be used on a cordless drill. but at low speeds. Includes brushes with diameters of Ø 8-9-10-11-12-13-14-15-16-17-18-19 mm. In a neat plastic case.