Hoppe's No. 9 Traditional Lubricating Oil is high-viscosity oil that has been refined to perfection. It is extra-long lasting and does not harden or gum up. We created this to be the perfect oil to use after cleaning a firearm bore with Hoppe's Tradition No. 9 Gun Bore Cleaner by ensuring it neutralizes the cleaner and leaves behind an even coat of lubrication for lasting protection.