Rust-Oleum 190 Thinner is a clear, professional-grade solvent formulated for thinning and clean-up of polyurethane coating systems. Engineered specifically for use with Rust-Oleum 9400 System Aliphatic Polyurethane and 9800 System DTM Urethane Mastic, it ensures smooth application and optimal finish quality. Composed of aromatic hydrocarbons, esters, and ketones, this thinner provides excellent solvency performance.