G-Flex Epoxy 650-8G flex Epoxy Adhesive belongs in every boater's repair kit. Get a waterproof, flexible bond on plastic, fiberglass, aluminum, etc. The 650 8 kit gives you two 4 oz. bottles of the liquid epoxy. The 650 8 kit contains 4 oz. each of viscous liquid G flex 650 resin and hardener. Mixing ratio is 1: 1. Mixed G flex 650 is of a heavy "syrup" consistency. It will run off a vertical surface. 650 can be thickened with inert filling materials. G flex is a