Montana X-Treme Bore Solvent is uniquely formulated to remove all forms of fouling in today's high velocity firearms. Many successful competitive shooters and barrel manufacturers have endorsed Montana X-Treme as the best bore cleaning product available. Recommended for general firearm cleaning. Safe for all firearm applications. Excellent for handgun applications. Safe for use on actions and bolts. Montana X-Treme Bore Solvent is completely barrel safe and can be left in the barrel overnight if desired.