The IOSSO Eliminator Premium Bore Brush for .40/.41 Pistols (19003) are made with a fiber that is cobalt blue which is a stiffer grade of fiber that allows for back and forth action unlike traditional brass and bronze type brushes. The fiber lasts approximately 8 to 10 times longer than other brushes. The brush is wound tighter and has more fiber per inch than any other brush.

Specs:

8/32 Threading