The Micro Bore and Valve-Guide Brush Set from Innovative Products of America is designed for cleaning valve guides, tubes and bores. Durable and abrasive, the eight-piece set includes 9” long brushes with 1/8” to 1/2” diameters. The twisted wire provides increased cleaning action and the flexible shaft is ideal for hard-to-reach applications. Each brush is fitted with an extra-large finger loop for enhanced control.