Montana X-Treme Nylon Bristle Brush for Rifles (8/32 Thread) 6.5mm/.264 cal SPECIFICATIONS BRAND: MONTANA X-TREME CA PROP 65: YES CLEANING ITEM TYPE: BRUSHES MATERIAL: NYLON USAGE: RIFLE DESCRIPTION Montana X-Treme Cleaning Brushes are some of the toughest nylon brushes in the industry. They are made with very stiff, heavy duty bristles and a solid brass core to assure your firearms will get a superior cleaning with minimal effort on your part. Standard 8 x 32 thread.