Montana X-Treme Bore Cleaning Solvent is formulated to remove all forms of fouling in your high velocity firearm. Safe for all firearms. Endorsed by barrel manufacturers and top competitive shooters, Montana X-Treme's bore solvent is the best general-purpose gun cleaning product on the market today. Effective on carbon, lead and copper fouling, MTX Bore Solvent's proprietary buffered solution will not damage barrels. It may even be left in the bore overnight to remove especially stubborn copper deposits.