Varathane Spar Urethane protects outdoor wood projects from the damage of sun exposure and weathering. The oil-based formula resists scratches and stains and is designed to get ultimate UV and weather protection for outdoor wood projects with Rust-Oleum Varathane Premium Spar Urethane. This oil-based formula applies easily and provides powerful resistance against graying and weathering. Premium outdoor polyurethane coating continues to deepen its amber look over time to give wood objects a warm, classic look.