These premium brushes are made on a handle for quick and easy cleaning. The thick and stiff blue fiber holds its shape well and allows for back and forth action unlike brass and bronze type brushes. They may be used several times before becoming worn. The brushes are wound tightly to allow for more cleaning area per inch. When used with the Iosso Bore Cleaner and Iosso Gun Oil, it will remove nasty carbon burn and all other fouling, including copper and lead. The brushes are a Trademark of Iosso Products. Please note: Warning: This contains a chemical known to the State of California to cause birth defects, reproductive, or other physical harm. Wear gloves or wash hands after handling. For further information go to www.p65warnings.ca.gov.