Truly the first brush to clean the 6.5 Creedmoor Chamber. They are sized to close tolerance for precision cleaning. Made out of a distinctive blue fiber, which is thick, stiff and holds it's shape well unlike traditional brass and bronze type brushes. They may be used several times before becoming worn. Pack contains 2 brushes. Suggested cleaners to be used with this brush is the Iosso Bore Cleaner and the Iosso Triple Action Oil. The blue brushes are a Trademark of Iosso Products.