VERSATILITY AND QUALITY IN ONE - Sometimes simply called Sika 221 white, this one-component urethane caulk bonds to a range of substrates, including metals, plastics, and metal primers and coatings AGE RESISTANT - Formulated to resist the effects of aging to better perform at peak capacity no matter the conditions. Also resists elements such as seawater, diluted acids, and caustic solutions READY TO USE - The Sikaflex black sealant comes in a handy cartridge that fits easily on an electric, pneumatic or manual application gun, making accurate placement of adhesive paste quick and easy SAFE AND EFFECTIVE - Approved by the NSF for use in both drinking water systems and food production operations, so you can rest easy knowing there's no harmful level of chemicals PERFECT FOR INTERNAL SEALS AND BONDING - Use it for permanent seals that you can rely on. The paste also bonds to ceramic materials and cures quickly upon exposure to atmospheric moisture