J-B Weld 1oz Gray Marine Weld Epoxy Adhesive Kit is a specially formulated two-part epoxy cold weld system that provides for strong lasting repairs for bonding different or similar surfaces such as aluminum metal composites fiberglass and others. Marine Weld sets in 4-6 hours at room temperature and is fully cured to a dark grey color in 15-24 hours. Once cured it can be shaped tapped filed sanded and drilled and will retain its strength above or below the water s surface. Marine Weld has a 1:1 mixing ratio and tensile strength of 3960 psi.