Flexible sealing and lasting durability define Loctite SI 5900, Silicone Sealant, 300 ml Cartridge, designed for gasketing and leak prevention in metal, plastic, and composite assemblies. Its high-performance RTV silicone formula forms a tough, oil-resistant seal that withstands vibration, thermal cycling, and exposure to water and chemicals. The easy-to-apply cartridge provides smooth, uniform flow for clean, precise application. Once cured, it maintains flexibility without shrinking or cracking, ensuring long-term reliability in dynamic joints. Ideal for marine engines, industrial equipment, and metric fabrication, this sealant delivers dependable sealing strength in demanding environments.