Cures fast especially in cold weather. For builders and boatyards. Use above or below waterline, on fiberglass, wood or metal. Type P (pourable) is for deck or horizontal seams. Type H (heavy) is for application by knife. Sandable after curing. True elastomeric sealant. Waterproof. Resists oil, gas, salt water, weather and aging. Type H requires no priming except on oily wood, teak or steel. No priming is needed for type-P. Made from Thiokol’s LP polysulfide polymer.