12 New Stiff Hair Wheel Brushes. This a new set of 12 stiff hair wheel brushes. These are ideal for polishing and cleaning all kinds of metals. Each is mounted on a mandrel with a 1/8 (3 mm) shank. Each brush measures approximately 1 (25.5 mm) in diameter. FindingKing works hard to update our descriptions and pictures of our merchandise. As part of a process of ongoing innovation by our suppliers, newer versions of the item shown may be shipped before we are able to complete an update. As a result there may be a slight variation in color and design.